Sub-national elections in Australia, particularly in small states like South Australia, tend not to warrant extensive national attention. They are seen as anachronistic, and not representative of wider national trends and opinions – they are second-order elections fought on state level issues and personalities. The 2026 South Australian election by contrast, represents a rare case of a state level election that offers insight into the current state of the national party system. One Nation’s landmark performance came amidst a national polling surge, and their campaign messaging was driven by national issues such as immigration and cost of living . Further, One Nations’ national leader Pauline Hanson was the central figure in the party’s campaign, suggesting that state specific factors may have been somewhat secondary in One Nation’s challenge to the party system.
The incumbent Labor Government led by Peter Malinauskas won re-election with 34/47 Lower House seats – a record for the party. Despite the magnitude of the ALP’s victory – it is the composition of the Opposition vote which offers potential insights into the trajectory of the Australian party system. This election marks the first time since the formation of the modern two-party system Labor and the Coalition parties have not come first and second in terms of seat or vote share, with One Nation winning 22.9% and four lower house seats, compared to the Liberal’s 18.9% and five seats. Whilst the Nationals formed official opposition after the 2022 WA Election, and One Nation achieved a similar vote surge in the 1998 Queensland Election – neither of these elections represented the same level of existential threat from a third-party challenger to one of the two traditional major parties.
The South Australian election of 2026 offers key insights into the potential trajectory of the national party system in three ways. First, it demonstrates that One Nation can turn high polling support into votes, and in significant enough numbers to gain representation in majoritarian lower houses. Second, it suggests that One Nation’s surging support presents a particular challenge for the Coalition – as the party’s strongest support is concentrated in rural and regional seats traditionally dominated by Liberals and Nationals. Third, it demonstrates that whilst concentrated in rural and regional areas, One Nation has the potential to supplant the Coalition as Labor’s competitor in metropolitan seats. In particular, South Australian results suggest One Nation poses a bigger threat to Labor in its traditional outer suburban heartlands than the Coalition – opening the potential for a larger political battlefield in future elections.
