(Updated 8 December – Schubert Liberal member Ashton Hurn will be elected new Liberal Leader unopposed. Post has been updated with maps colour coded by holding party.)
South Australian Liberal Leader Vincent Tarzia has today resigned citing the pressure of leading the Liberal Party while trying to raise a young family. He still intends to contest his marginal seat of Hartley at the looming state election.
Given Hartley has a margin of only 3.6%, it is hard to see how Tarzia can retain his seat at the state election in March given polls are predicting a double-digit swing to Labor.
Inside this post I have published an electoral pendulum for the state election to be held on 21 March.
The Labor Party easily won the won the 2022 election, ending the one term government of Liberal Premier Steven Marshall.
Labor won 27 of the 47 seats in the House of Assembly. Labor has since gained two more seats at by-elections, winning Steven Marshall’s former seat of Dunstan in March 2023, and Black formerly held by his successor David Spiers in November 2024.
Of the 16 elections since 1970, Labor has won 12 to the Liberal Party’s four. The electoral geography of South Australia has often delivered government to Labor without the party achieving a majority of the two-party preferred vote.
But that wasn’t a problem in 2022 with Labor recording 54.6% of the state-wide two-party preferred vote. It was Labor’s second best result since 1970, bettered only by Mike Rann’s landslide re-election in 2006.
Labor Premier Peter Malinauskas is immensely popular. October’s Demos opinion poll had him leading Tarzia as preferred Premier 58% to 19%. The poll had Labor on 66% of the two-party preferred vote.
If repeated at the state election on 21 March, Malkinauskas will challenge the greatest landslide election record set by former WA Labor Premier Mark McGowan in 2021.
After gaining the seats of two Liberal leaders since 2022, Labor will be keen to add a third in Tarzia’s seat of Hartley. And maybe go for fourth depending on who emerges as the new leader.
On current polling Labor will win every seat on the plain of Adelaide and could even push up into the Adelaide Hills given Labor’s good result in Mayo at the Federal election.
The Liberal Party will do well if it can retain a handful of rural seats. Even in rural areas, the party is facing serious challenges from Independents, and several former Liberal members already sit on the cross bench.
Already Labor seems to be taking the opportunity for generational change, something the party did very well before losing office for a single term in 2018. Five high profile Labor members including several ministers have announced they will retire. Two decade veteran Tony Piccolo will also shift from his safe seat of Light to try and win the Liberal seat of Ngadjuri (formerly Frome).
Three Liberals have announced their retirement, and all hold seats that Labor is strongly placed to win.
Inside the post I have a new electoral pendulum that takes account of the redistribution completed earlier this year. I also include notes on some of the more complex contests where new boundaries, defections and departures complicate the analysis.
| Labor Seats (29) | Liberal Seats (16) | ||
|---|---|---|---|
| % Margin | District | % Margin | District |
| ALP 0.8 | Dunstan (by-elec gain) | LIB 1.1 | Stuart (IND held, see notes) |
| ALP 2.5 | Gibson | LIB 1.4 | Morialta |
| ALP 3.4 | Davenport | LIB 2.2 | Unley |
| ALP 4.0 | King | LIB 2.6 | Heysen |
| ALP 4.0 | Waite | LIB 3.2 | Ngadjuri (previously Frome, see notes) |
| ALP 5.4 | Newland | LIB 3.5 | Kavel (see notes) |
| ALP 5.6 | Elder | LIB 3.6 | Hartley |
| ALP 6.2 | Adelaide | LIB 4.5 | Morphett |
| ALP 9.9 | Black (by-elec gain) | LIB 4.8 | Colton |
| ALP 10.0 | Torrens | LIB 5.1 | Hammond |
| ALP 11.5 | Lee | LIB 6.7 | Finniss (0.7 v IND) |
| ALP 11.9 | Wright | LIB 8.2 | Bragg |
| ALP 12.8 | Florey | LIB 11.9 | Schubert |
| ALP 13.8 | Mawson | LIB 13.8 | Mount Gambier (see notes) |
| ALP 14.5 | Enfield | LIB 14.0 | Narungga (IND held, see notes) |
| ALP 14.8 | Badcoe | LIB 17.2 | Chaffey |
| ALP 15.7 | Hurtle Vale | LIB 20.3 | Flinders (3.0 v IND) |
| ALP 16.3 | Playford | LIB 22.6 | MacKillop (see notes) |
| ALP 17.2 | Reynell | ||
| ALP 18.4 | Taylor | Independent (2) | |
| ALP 18.8 | West Torrens | % Margin | District |
| ALP 19.1 | Cheltenham | IND 8.1 | Narungga (v LIB) |
| ALP 19.7 | Giles | IND 14.1 | Stuart (v LIB) |
| ALP 19.8 | Kaurna | ||
| ALP 19.9 | Ramsay | ||
| ALP 20.1 | Light | ||
| ALP 21.7 | Elizabeth | ||
| ALP 21.8 | Port Adelaide | ||
| ALP 24.8 | Croydon | ||
Notes: Margins shown for Labor and Liberal seats are based on two-party preferred results. Independent held seats are shown with relevant two-candidate preferred margins against the Liberal Party. Alternative two-candidate preferred margins are shown for several seats in brackets. All margins are re-calculated post redistribution.
Margins for Black and Dunstan are based on Labor gains at by-elections since 2022. More information on both below. Bragg is shown with its margin from the 2022 state election, not the subsequent by-election where it was retained by the Liberal Party.
The Liberal Party can be viewed as holding 16 or 13 seats depending on how you choose to classify Independent seats. Kavel and Mount Gambier are shown as Liberal-held with two-party margins based on the departure of incumbent Independents. MacKillop is also shown as Liberal held but the sitting member has left the Liberal Party and will re-contest as an Independent.
Notes on Selected Districts
Black: Gained by Labor at a November 2024 by-election following the resignation of former Liberal Leader David Spiers. The 2022 Liberal margin was 2.7%.
Dunstan: Gained by Labor at a March 2023 by-election following the resignation of former Liberal Premier Stephen Marshall. The 2022 Liberal margin was 0.5%.
Finniss: Liberal MP David Basham will again be challenged by Independent Lou Nicholson.
Flinders: Based on Port Lincoln and the rural Eyre Peninsula, Flinders has traditionally been one of the Liberal Party’s safest seats. Liberal MP Sam Telfer was first elected in 2022, easily winning the two-party preferred contest but run a much closer two-candidate preferred race of 3.0% by independent Liz Habermann. Telfer faces another high profile Independent challenge in 2026 from Port Lincoln businesswoman Meghan Petherick.
Kavel: Liberal turned Independent MHA MHA Dan Cregan was easily re-elected in 2022. He is retiring at the 2026 election. The margin used in the pendulum is the Liberal two-party preferred margin versus Labor.
MacKillop: MHA Nick McBride has resigned from the Liberal Party and will re-contest as an Independent.
Ngadjuri: New name for the former electorate of Frome. The new boundaries have significantly reduced the Liberal margin from 8.1% to an estimated 3.2%. The seat will see a contest between two sitting MHAs in 2026 with Liberal MP Penny Pratt being challenged by Labor’s Tony Piccolo who has been the very popular MHA for the neighbouring seat of Light since 2006.
Stuart: Won by Independent Geoff Brock in 2022, switching seat to follow his political base in Port Pirie after it was transferred from his former seat of Frome. Brock had previously represented Frome since 2009. The margin is an estimate trying to take account of significant boundary changes.
Mt Gambier: Currently vacant. Independent MLA Troy Bell has been charged and convicted for theft of public money. This disqualified him from sitting as an MHA and he is currently in custody. Mount Gambier will be vacant until the state election. The 2022 Liberal two-party preferred margin versus Labor is used in the pendulum.
Retiring Members
Colton: (LIB 4.8%) Former paralympic swimmer and Liberal MP since 2018 Matt Cowdrey is retiring.
Elizabeth: (ALP 21.7%) Labor MHA since 2010 Lee Odenwalder is retiring.
Kavel: (LIB 3.5%) Former Liberal turned Independent MHA since 2018 Dan Cregan is retiring. He won with a 25.4% margin versus the Liberal Party but on new boundaries the estimated Liberal margin versus Labor is 3.5%.
Lee: (ALP 11.5%) Labor MP since 2014 and former Treasurer Stephen Mullighan is retiring.
Light: (ALP 20.1%) Vacant seats as Labor MHA since 2006 Tony Piccolo is contesting the neighbouring Liberal seat of Ngadjuri.
Mawson: (ALP 13.8%) Speaker Leon Bignell is retiring. He has represented Mawson since 2006 though the seat has undergone major boundary changes, moving out of the metropolitan area and extending to Kangaroo Island since 2018. The chopping and changing of boundaries has seen Bignell increase his margin at every election.
Morialta: (LIB 1.4%) Liberal MHA since 2010 John Gardiner is retiring.
Mount Gambier: (LIB 13.8%) Vacant seat following the conviction and disqualification of Troy Bell. Without Bell the seat becomes a notional Liberal seat.
Port Adelaide: (ALP 21.8%) Former Deputy Premier and MHA since 2012 Susan Close is retiring.
Torrens: (ALP 10.0%) Labor MHA since 2014 Dana Wortley is retiring.
Unley: (LIB 2.2%) Liberal MHA since 2006 David Pisoni is retiring.
Electoral Maps, Holding Parties and Margins
You can hover or tap the maps below for more information on the seat margin, sitting member and the contest for 2026.
This will be a very interesting election because it could possibly be the first time that a teal independent would be elected at any level of government in South Australia. It could also be the first time that we would see a lower house Greens MP be elected. I think it’s kinda hilarious that the only seats that the Liberals are expected to retain align perfectly with the federal seat of Barker.
Hi Antony,
Could I ask how you were able to calculate the two-party preferred margins for your 2026 Pendulum for the six seats that, in 2022, were ‘non-classic’ seats? (I.e. the six seats where the ALP did not make the final two – Finniss, Flinders, Kavel, Mount Gambier, Narungga, and Stuart.)
I understand that, unlike following previous elections, the ECSA only released two-party preferred results by district for the non-classic seats, rather than by polling place. I assume that your task – i.e. calculating new margins following the redistribution – was made more difficult in these (and adjoining) districts without polling place data for the rethrows.
COMMENT: The polling place 2PP data was made available but I don’t think it is on the ECSA website.
I’m very much looking forward to seeing what the numbers are looking like right now. I haven’t found any recent polling but you’d have to imagine the writers week fiasco is going to effect the numbers and I’m quite curious if the greens will get some voters switching to them, maybe even enough to become the minority leader with the liberals and one nation splitting the voters.
COMMENT: The Greens top five votes in 2022 were 20.7% in Heysen, 18.7% in Unley, 17.2% in West Torrens, 13.7% in Dunstan and 13.5% in Adelaide. I think Heysen would be the one worth watching as the Labor primary vote is probably too high in the other seats.
Yeah and then One Nation splitting the conservative vote… Poor Liberals.
I would be very interested to see some polling now that One Nation is fielding candidates in every seat.. If Federal polling is reflected at a state level.. then One Nation could very well be the next opposition party in South Australia.
Is there any modelling?
COMMENT: The last SA poll published in December has Labor on 41%, Liberal 21%, Greens 12% and One Nation 13%. All the surge in One Nation support has been in polls since the start of January. If that is reflected in SA polling it will be dire for the Liberal Party.
Hi Antony,
I would like to know your thoughts on the state seat of Port Adelaide in the upcoming state election. It is a safe ALP seat but the current member will be retiring at the election and the current Mayor of Port Adelaide Enfield Council has announced that she will be running in the election as an Independent Candidate.
Thanks
COMMENT: Not knowing the Mayor I really couldn’t offer an opinion. In retirement I have given up doing election guides. That honour is now with Casey Briggs and you can find his summary of Port Adelaide here.
Port Adelaide Mayors have run before. Gary Johanson was Mayor of Port Adelaide Enfield for 12 years and contested neighbouring Lee as an Independent in 2014 and Port Adelaide as an SA Best candidate in 2018 without success. He also ran as an Independent without success at the 2020 Enfield by-election. I offer no opinion on the qualities of the current Mayor, but with voluntary voting for SA local government elections, Mayor’s are not always well known to average voters.
Would agree with you Antony regarding the historical results. Unlike the big east coast states (NSW, Victoria and Queensland) where local government elections are compulsory, council leaders/mayors in the other states tend to have less name recognition and will find it harder to compete in statewide or national elections.
You discuss Flinders: Based on Port Lincoln and the rural Eyre Peninsula, Flinders has traditionally been one of the Liberal Party’s safest seats.
I suppose it all depends on how long you consider it takes for a tradition to be established. Peter Blacker was the National Party Member for the seat from 1973 to 1993, winning comfortably each time. He was a thorn in the side of the SA Liberal Party, and only lost his seat in the Lib landslide at the end of the Bannon / Arnold Labor government.
COMMENT: Flinders has a long history as one of the safest conservative seats in the state. It was taken from the Liberal and Country League at the 1973 election by the National Party’s Peter Blacker. He held it on his strong personal vote until being swamped by the swing against Labor in 1993. He also had to overcome the first ‘fairness’ redistribution ahead of the 1993 election that appended Kangaroo Island to Flinders, adding a few thousand Liberal voters. It was removed in 1977.