The Impact on Senate Election Results of Abolishing GVTs – the Lessons for Victoria

Over the next week I will publish several posts looking at the abolition of Group Voting Tickets (GVTs) in Victoria and the implications this has for the state’s Legislative Council election in November.

Work I’ve undertaken in the past, about Senate elections both before and after the abolition of GVTs, produces clear conclusions.

Abolishing GVTs will increase the importance of first preference votes and diminish the value of preference transfers. Abolishing GVTs advantages parties that campaign for votes and disadvantages those that rely on deals and transfers to be elected.

Abolishing GVTs also ends the ability of parties to conspire and use GVTs to block the election of high polling parties. It also stops parties using GVTs to elect low-polling parties that few voters have heard of into important upper house balance of power seats.

The key aim of abolishing GVTs is to end party control over between-party preferences and leave it to voters to make the decision. With 95% of votes tied up in party tickets, too many elections had been decided by opaque preferences deals that voters had little knowledge of. A new form of above-the-line (ATL) voting was created allowing voters to show preferences for parties rather than candidates. Voters still had the option to vote below-the-line (BTL) for individual candidates of any party.

In other states this has been implemented with full optional preferential voting. A voter must indicate a first preference for a formal vote, but further preferences were optional. At elections conducted under the new rules, only a third of ATL ballot papers have preferences beyond ‘1’ and exhausted preferences have come to play a part in deciding who wins the final seats. (See my previous post that covered experience with the change in NSW.)

By contrast, the Senate instructions after the abolition of GVTs has been to mark at least six preferences, though a savings provision allows any first preference vote to remain formal. Under these instructions, around 95% of ballot papers are completed above the line (ATL) with between-party preferences. Given the exhaustion rate of preferences for minor party votes, there hasn’t been much difference between the role of preferences in the two ballot marking systems.

Abolishing GVTs makes it nearly impossible to win from a low vote AND from behind on preferences. Abolishing GVTs does not prevent a party winning from a low vote, nor prevent a trailing candidate from winning on preferences, though it does make it harder. But is becomes extremely difficult to do both at the same time.

A party winning from a low vote is possible without GVTs if there is an even split of vote between remaining parties. The United Australia Party’s Ralph Babet won a Victorian Senate seat in 2022 from only 0.28 quotas (4.0%). This was because there were five parties between 0.20 and 0.28 quotas competing for one seat. Without GVTs, preference flows were relatively weak and Babet maintained his lead to win the final seat. Preferences were not responsible for his victory.

And coming from behind is possible. In NSW at the 2025 Federal election, strong preference flows from the Coalition and small right-wing parties allowed One Nation on 0.42 quotas (6.1%) to pass Labor’s third candidate on 0.63 quotas (9.1%).

Without GVTs, the classic 2013 Victorian Senate case of Ricky Muir (Australian Motoring Enthusiasts Party) on 0.5% defeating Helen Kroger (Liberal) on 11.6% would be impossible. Muir’s election was the equivalent of a lower house candidate on 1.7% defeating a candidate with 40%.

As One Nation showed in 2025, is is possible for a candidate with two-thirds of another candidate’s vote to come from behind and win on preference transfers. Voters still have their say on preferences, but without GVTs, results can’t be engineered. Muir’s case of winning from behind with only one-23rd of the winning candidate’s vote is absolutely impossible without GVTs.

And to date, every jurisdiction except except Victoria has understood this inherent problem with GVTs and abolished them. Next week it appears Victoria will be the last to join the club.

Based on One Nation’s two come from behind Senate victories in 2025, I think around 0.4 quotas is the minimum a party needs for victory, 6.5% translated into Victorian Legislative Council numbers. That’s unless you get a case like Ralph Babet’s where a seat remains to be filled and all remaining parties have a low vote.

Looking at how many parties have been elected from trailing positions, the difference produced by the abolition of GVTs for Senate elections is clear.

At the 2013 half-Senate election, the last to use GVTs, 9 of the 36 state Senate positions were won by trailing candidates. At three half-Senate elections since the abolition of GVTs, only 2 of 108 state Senate seats have been won by trailing candidates.

And both of those trailing wins were aided by Senate instructions to mark 6 preferences. Trailing wins may be even harder under instructions for ‘1’ with further preferences optional.
Read More »The Impact on Senate Election Results of Abolishing GVTs – the Lessons for Victoria

FED2026 Redistributions – South Australian Boundaries Finalised

The South Australian redistribution of electoral boundaries has been finalised this morning. The Commission has abandoned a swap of suburbs between Kingston and Mayo, as well as the transfer of an area from Spence to O’Donoghue (formerly Grey). This means that Kingston and O’Donoghue retain their former boundaries without change.

The Draft boundaries released in March produced only minor changes to the boundaries used at the last three federal elections. Those changes have now been reduced with the Spence to O’Donoghue change reversed and the proposed suburbs swap between Mayo and Kingston abandoned.

South Australia was reduced from 11 to 10 House of Representatives seats by the 2017 redistribution. The current redistribution retains 10 seats and was triggered by the rule requiring boundaries to be re-drawn every seven years. The reason for periodic re-draws is to account for differing patterns of population growth, to bring all electorates back within permitted variation from quota.

Barker pushes closer to Adelaide and gains 3,365 voters around Woodchester from Mayo. Grey has been re-named O’Donoghue but proposed boundary changes abandoned. Population growth in the Adelaide Hills has seen Mayo shed voters to Barker and around 6,275 to Boothby. Adelaide’s outer north has also been growing rapidly and Spence has lost 14,043 voters in Brahma Lodge and Salisbury to Makin. Proposed changes to Kingston have been abandoned and Adelaide, Hindmarsh and Sturt retain their unchanged status from the draft phase.

The table below has been now re-calculated for the final boundaries.

South Australia Federal Redistribution – Summary of New Margins
District Old Boundaries New Boundaries Shift
Adelaide ALP 19.1% ALP 19.1% unchanged boundaries
Barker LIB 13.0% LIB 12.7% 0.3 to Labor
Boothby ALP 11.1% ALP 11.1% no change
Hindmarsh ALP 16.3% ALP 16.3% unchanged boundaries
Kingston ALP 20.7% ALP 20.7% unchanged boundaries
Makin ALP 14.7% ALP 15.3% 0.6 to Labor
Mayo (2-Party) ALP 5.0% ALP 4.8% 0.2 to Liberal
Mayo (IND v ALP) IND 14.9% IND 15.5% 0.6 to Independent
O’Donoghue (formerly Grey) LIB 4.6% LIB 4.6% unchanged boundaries
Spence ALP 15.3% ALP 15.2% 0.1 to Liberal
Sturt ALP 6.6% ALP 6.6% unchanged boundaries

Read More »FED2026 Redistributions – South Australian Boundaries Finalised

FED2026 Redistributions – Tasmanian Boundaries Finalised

The new electoral boundaries for Tasmania have been released today.

Reading through the proposed changes, the major changes to Clark, Franklin and Lyons in southern Tasmania have been agreed to. But there are changes in the north with Break O’Day council being moved into Bass.

There is also a proposed name change which has triggered the calling of a new round of comments specifically about changing the name of Franklin to Tongerlongter. As the proposal explains the name –

Following its deliberations, the augmented Electoral Commission proposes renaming the electorate of Franklin in honour of Tongerlongeter (c. 1790-1837), a Poredareme man of the Oyster Bay nation and a prominent Aboriginal leader whose Country encompassed much of south-east Tasmania, including areas within the reconfigured electorate boundaries. The name ‘Franklin’ is proposed to be retired.

Earlier I tweeted that the draft boundaries had been abandoned. That was confusion on my part by opening the wrong map and thinking that was the reason for calling a new round of submissions. It is rare for redistributions to engage in this extra consultation step. It appears the consultation is over the name change alone so the boundaries appear to be otherwise final.

The draft boundaries released earlier this year produced massive changes to the electorates of Clark, Franklin and Lyons. You can read more details in my post on the draft boundaries.

The table below summarises the two-party preferred margins between Labor and Liberal in the five divisions. I’ll go into more detail on the Independent positions in Clark and Franklin inside the post.

Tasmania Federal Redistribution – Summary of 2-Party Preferred Margin Changes
District Old Boundaries New Boundaries Shift
Bass ALP 8.0% ALP 8.3% 0.3 to ALP
Braddon ALP 7.2% ALP 7.2% Unchanged
Clark ALP 20.9% ALP 20.2% 0.7 to LIB
Franklin ALP 19.4% ALP 18.7% 0.7 to LIB
Lyons ALP 11.6% ALP 12.7% 0.9 to ALP

Read More »FED2026 Redistributions – Tasmanian Boundaries Finalised

Reports that Victoria is set to Abolish Group Voting Tickets

(Update Wednesday 29 July: – Legislation has been introduced today and will be debated and passed by the Assembly this afternoon. The legislation abolishes group voting tickets and adopts a similar method of ATL voting to the Senate. Voters are required to mark 5 ATL preferences and there is a savings provision so that any vote with at least a valid first preference vote remains formal. There is no change to the Victorian method of BTL voting where voters are required to complete preferences for five candidates.)

Two weeks ago I published a post highlighting that if Victoria wanted to abolish group voting tickets (GVTs) for the 2026 Legislative Council election, legislation had to be passed at the next sitting of parliament in the last week of July.

As I outlined in the post (you can find it at this link), abolishing GVTs would bring Victoria in line with the Commonwealth, New South Wales, South Australian and Western Australian parliaments. It would also implement a recommendation made twice in the last four years by the Victorian parliament’s Electoral Matters Committee.

Both The Age and Herald-Sun reported over the weekend that GVTs will be abolished and voters allowed to indicate their own preferences with an above-the-line (ATL) vote. What the reports don’t make clear is whether Victoria will adopt fully optional preferential voting as used in NSW, SA and WA. The alternative would be to copy the Senate model where ballot paper instructions are to complete a minimum number of ATL preferences. The Senate model still allows any vote with a valid ATL first preference to remain formal in line with ballot paper instructions for the GVT system.

The number of members to be elected per region may lean the Victorian decision in favour of the Senate system.

NSW, SA and WA elect their Legislative Councils using a state-wide electorate. NSW elects 21 members, South Australia 11, and Western Australia 37. A single ‘1’ vote in these systems is enough to produce a very proportional result. Over six elections since the NSW system was reformed, only twice have preferences altered the party elected as the 21st member. Two SA elections elections have seen preferences play no part in the result, while the first WA election after reform saw preferences change only one of the 37 members elected.

The complication in Victoria is members are not elected state-wide. The Legislative Council consists of five members elected from each of eight regions. The quota for election is a high 16.7%. A high quota makes it much harder to match the number of members elected by party in each region to the proportion of votes by party.

As with the Senate, where six members are elected per state, there may be an argument to encourage more ATL preferences to ensure the members elected reflect first preference votes and the preference intent of voters for excluded parties.

The Senate rule to mark at least six preferences encourages voters to complete preferences. At the 2025 Victorian Senate election, 83.4% of voters marked six preferences. Only 1.9% of voters marked a single first preference, a vote that remains formal under Senate voting rules.

Contrast this with lower preferencing rates at interstate Legislative Council experience where only a third of ballot papers have preferences. If fully optional preferential voting were adopted, then clearly there would be fewer preferences playing a part in determining the final seats in each region. It is a matter of opinion whether this is a good or bad outcome.

Fully optional preferences would work without difficulty if Victoria were electing 40 MLCs from a state-wide electorate. But Victoria can’t switch to state-wide election without a referendum, so the five members by eight regions model will be used in 2026.

In this post I’ll first summarise why the GVT system is so wrong using past election results. I’ll also look at evidence from NSW elections about how the Senate’s minimum preference numbers rule has caused more voters to complete further preferences at Legislative Council elections.Read More »Reports that Victoria is set to Abolish Group Voting Tickets

FED26 Redistributions – Final Boundaries Released for A.C.T.

The final boundaries for the ACT have been released. Maps and numbers of voters transferred have not been released, but I have managed to estimate new margins using data published with the draft boundaries.

In short, nothing much changes. The table below summarise the margins for the ACT’s three electorates.

ACT Federal Redistribution (Final) – Summary of Margin Changes
District Contest Old Boundaries New Boundaries Shift
Bean 2-Party ALP 19.3% ALP 19.4% 0.1 to ALP
Canberra 2-Party ALP 26.4% ALP 26.4% No change
Fenner 2-Party ALP 22.1% ALP 22.1% No change
Bean ALP v IND ALP 0.3% ALP 0.2% 0.1 to IND
Canberra ALP v GRN ALP 19.5% ALP 19.5% No change

There’s more details on each electorate inside the post.
Read More »FED26 Redistributions – Final Boundaries Released for A.C.T.

Time Running Out for the Victorian Government to Abolish Group Voting Tickets

10 August – party lists updated

The long-term decline in support for Australia’s traditional parties, combined with surging support for One Nation, is creating uncertainty over who will form government after November’s Victorian state election.

Opinion polls show Labor, the Coalition and One Nation all under a third of the vote. It is difficult to translate this three-way split of votes into a seat prediction, but it points to defeat for Labor if the Liberal and National parties co-operate with One Nation on preferences.

Seats not votes determine who forms government and whether it is a majority or minority government. Turning votes into seats will come down to order of exclusion and preference flows between three or four competing candidates in each seat.

The outcome in the Legislative Council, the upper house elected by proportional representation, would be easy to pick if it was elected from a state-wide electorate like other mainland states.

But Victoria’s Legislative Council is divided into eight regions electing five members each. Five regions cover most of metropolitan Melbourne. Three others extend like spokes to the corners of the state, covering rural and regional Victoria but including some outer Melbourne suburbs.

Having only five members per region makes it very difficult to match members elected to party vote share. The high 16.7% quota makes preferences critical for turning surplus to quota votes into extra seats.

And there is another problem. Despite numerous warnings and recommendations, electoral law in Victoria still mandates that the discredited Group Voting Ticket (GVT) system will be used for November’s upper house election.

Unless the law is changed, as recommended by committee and as already changed elsewhere, the ‘preference whisperers’ will be back in business.

We have had four Federal elections since GVTs were abolished for the Senate. Since 2016 voters have grown used to numbering their own party preferences when voting above-the-line (ATL). But as it stands today, and as I explained before the last Victorian election in 2022, any ATL preferences will be discarded and replaced by the GVT of the voter’s first choice party.

Twice this term the Electoral Matters Committee has recommended that group voting tickets to be abolished. Despite support for the move from the Opposition and Greens, nothing has happened. The Electoral Act retains group voting tickets as the method by which above-the-line votes are handled in the count.

If something isn’t done in the next month, shady backroom deals will determine the composition of the Legislative Council. And if the past is anything to go by, there could be half a dozen crossbench members elected from unknown parties recording only a tiny first preference vote.

If no one party wins a majority in the lower house, the prospects of an upper house occupied by political unknowns can only complicate the task of trying to govern Victoria for the next four years.

The Legislative Council is meant to be elected by proportional representation. But with more than 90% of votes locked into pre-arranged group voting tickets, proportionality is distorted and political power is delivered into the hands of the small cabal of party negotiators who arrange the GVT preference deals.

To avoid the upper house election descending into farce, it’s time for the Allan government to act and abolish group voting tickets.

As I explain in this post, the Electoral Commission has set a deadline for changing the law ahead of the election. And as I also explain, the last minute rush of party registrations and proposed party name changes show that the preference harvesting game will kick off if GVTs are not abolished. Read More »Time Running Out for the Victorian Government to Abolish Group Voting Tickets

ABS Population Statistics confirm no change to State Representation for the Next Federal Election

(Update 23 July: the Electoral Commissioner’s determination has been published in the government gazette today. You can find it here.

The official calculations are the same as the ones in this post except the Territories have slightly higher numbers after adding in Norfolk Island and Jervis Bay to the ACT, and Christmas Island and Cocos Keeling Island to the Northern Territory.)

(Original post from 18 June follows)

The Australian Bureau of Statistics (ABS) has today released state population figures for the last quarter of 2025. These numbers confirm that there will be no change to state representation in the House of Representatives for the next Federal election.

The interest had been whether Queensland would be entitled to an extra seat for its twice delayed redistribution of Federal electoral boundaries.

Under the 7-year rule, Queensland had been due to have a redistribution begin in March 2025. Clearly this wasn’t possible with a Federal election due.

The redistribution should have started after the election along with the redistributions in Tasmania, South Australia and the ACT.

The Queensland redistribution was officially deferred until after a determination on state representation by the Electoral Commissioner to be made in July 2026

If Queensland was going to be allocated a 31st seat, there was no point starting a redistribution for 30 seats. The Australian Bureau of Statistics figures released today confirm that Queensland will remain with 30 members.

No change in state numbers will become official in July when the Australian Electoral Commissioner Jeff Pope issues a formal determination of the number of House members to be elected form each state and territory. The determination is always made one year after the first sitting of the House of Representatives following an election.

Commissioner Pope has no personal choice in making the determination as the method is strictly defined in law. For states the Commissioner will apply the formula set out in Section 24 of the Constitution. For the Territories the Commissioner will use the formula set out in the Electoral Act. The Constitution also states that the Commissioner will use the “latest statistics of the Commonwealth”, a phrase the High Court and Parliament has determined will be the quarterly population statistics. Today’s ABS release of last December’s statistics is the population numbers that Commissioner Pope will use.

The precise calculations around how seats are allocated is explained inside this post.

Once the new numbers are officially announced at the end of July, a redistribution of Queensland federal boundaries will commence based on re-drawing the existing 30 seats. The new boundaries will be in place for the next election due in 2028.Read More »ABS Population Statistics confirm no change to State Representation for the Next Federal Election

The Financial Review’s Inaccurate Preference Analysis

One Nation’s polling surge has triggered an intense dissection of recent election results.

One Nation made the final preference count at the recent Farrer by-election. One Nation also finished in the final preference pairing in more than half of South Australian electorates at the state election in March. These results offer a mine of data where One Nation is a recipient of preferences rather than a provider.

Trying its luck dissecting the results on 7 June was the Australian Financial Review. It published an analysis piece on Farrer and South Australia headlined “How One Nation is winning the preferences war (with the Greens’ help)”.

As I will outline in this post, the article has confused published preference distribution data with more accurate but unavailable preference flow data. And the remark about Greens preferences isn’t backed by my analysis of the data.

The article was published three days before the Farrer flow data was released and the South Australian analysis has been attributed to preference flow data that is not available.

With the South Australian results, the article uses preference transfer data to draw some odd conclusions about Green preferences, and illustrates flows for other parties that aren’t justified given the quality of the data.

That the analytical problems, which I’ll explain in this post, have passed without much comment from anyone is due to the published chart included below. The chart tries to show SA preference flows from other parties to One Nation.

The chart’s meaning and data source are hard to unravel, but mirth has been the main reaction due to the inclusion of imaginary party names. It has caused the AFR to publish a correction and remove the chart from the on-line article.

LCP, an acronym for the Legalise Cannabis Party, is rendered as the Liberal Catholic Party. FGA, for Sarah Game’s Fair Go Australia, is transformed into the Family Guardian Association.

To the best of my knowledge, neither party name has ever been used in Australia.

It looks to me like a case of AI ‘hallucination’, AI asked to convert codes into party names and guessing it wrong. I doubt a human made those errors.

But enough cheap shots over party names. What I really want to explain is the article’s problems with data source and analysis.

With Farrer, I want to explain how the chart used to demonstrate the composition of One Nation’s winning vote uses the wrong data. It results in an incorrect emphasis on whose preferences were responsible for One Nation’s final margin.

With South Australia, the available data cannot be used to isolate the preference flows shown in the now deleted AFR chart. And the data that is available does not support the headlined conclusions about Greens preferences.

In both cases the problem comes down to limitations on how you can use preference transfer data from published distributions. The data must be treated with caution and can’t be automatically compared with more accurate preference flow data.Read More »The Financial Review’s Inaccurate Preference Analysis

2026 – Farrer By-election – Final Count Data Released

This morning the AEC finalised counting for the Farrer by-election with the release of detailed preference data.

It answers what I thought was a key question in the result – whether there was a difference between Liberal and National preference flows to One Nation. It was not possible to answer this question using the previously released full distribution of preferences.

Preference flow data tallies destination preferences from the primary votes for each excluded candidates to one of the final two candidates. In Farrer this data tallies preferences from ten excluded candidates to One Nation’s David Farley and Independent Michelle Milthorpe, the final pairing of candidates. Preference flow data ignores the intermediary stages published as part of the formal distribution of preferences.

The data released today reveals a difference in preference flows by supporters of the two Coalition parties . Liberal voter preference flows to One Nation were 59.0% compared to 69.1% for Nationals voters.

The flow data also reveals that One Nation’s David Farley did not need Liberal preferences to win. In the full distribution of preferences, Farley did not pass 50% until the Liberal candidate was the last excluded. Using the flow data where National preferences do not first flow through the Liberal candidate, Farley reached 50.2% on the flow of National preferences without the need for any Liberal preferences.

The question is whether the different flows tell us anything about how Liberal and National preferences would flow at a general election. In Farrer there was no Labor candidate in the final pairing. I suspect both National and Liberal preference flows to One Nation would have been higher in a final contest involving Labor rather than an Independent.

But it does suggest that Liberal preferences to One Nation will be weaker than those of National candidates. That was the case two decades ago in Queensland before the formation of the LNP. It in part reflects the different appeal of One Nation in rural electorates contested by Nationals versus the flows in urban electorates contested by Liberal candidates. One Nation polled a high enough first preference vote in Farrer for this difference not to matter. But a lower primary vote and weaker Liberal preferences would hamper One Nation hopes of winning urban seats.

Against this view, that the Liberal candidate drew top spot on the ballot paper with Milthorpe in second position suggests that the donkey vote may have played a party in the weaker Liberal preference flows to One Nation.

And it has to be remembered that preference flows from voters on the right of politics have always been weaker than from voters on the left. One Nation and the two Coalition parties rarely achieve the sorts of flows produced by the Greens in Farrer. Despite polling only 2.3% of the vote, Greens preferences flowed 91.8% to Independent Michelle Milthorpe. At general elections, Green voter preferences to Labor are consistently above 85%, a figure that the Liberal and National parties struggle to achieve from their supporters in three cornered contests.

I haven’t had time to pull apart the data by polling place, but the swing to One Nation was smaller in Albury, by far the largest regional centre in the seat. It was also in Albury where Liberal and Milthorpe support was strongest. Farley was better known in the west of the electorate where National support was also strongest. It may be the different preference flows reflect this familiarity with local candidates and the weaker One Nation support in Albury.

There’s more data on the preferences inside the post, along with an effort to graph the preferences data. Read More »2026 – Farrer By-election – Final Count Data Released