• DemosAU modelling shows how Labor and the Coalition could win more seats at the next election with a lower primary vote share than they received in 2025.
• For more information, check out our In the Know podcast.

Australia’s fragmented electoral landscape means relatively small primary vote swings could lead to disproportionate seat wins and losses, according to new modelling from DemosAU.

DemosAU’s recent MRP model, on polling of 9,343 voters conducted from late May to mid-July provided a central projection of 68 seats for Labor, 60 for One Nation, 13 for the Coalition, three for the Greens and six for independents and minor parties. 

This was based on the following primaries: Labor, 26, One Nation, 30, Coalition, 21, Greens 13 and Others 10

However, DemosAU Head of Research George Hasanakos said further modelling based on uniform changes from the original MRP results showed that with three parties now polling above 20%, small primary vote changes could have a big impact on the final result.

How a Higher ALP Vote Could Play Out

Mr Hasanakos said the modelling showed a 2 point lift in Labor’s Primary would bring the central projection to 75 seats, while a 4 point lift (to a primary of 30%) would see the party claim 85 seats, according to the MRP.

Meanwhile a primary of 32% (a -2.56% swing compared to 2025) would see the party claim 98 seats (a net gain of 4 seats). 

“The way the electorate is currently fragmented means Labor could suffer a negative primary vote swing compared to last election and still win more seats,” he said.

What Happens if the Coalition Vote Recovers

The modelling also shows that the potential for a right wing/non-Labor government increases when a portion of One Nation voters switch to the Coalition, because of the nature of preference flows between the two parties.

“One Nation voters are more likely to preference the Coalition than Coalition voters are to preference One Nation.”

“So a higher relative Liberal/National vote equals more seat gains, all else being equal,” he said.

The modelling shows a two point shift from One Nation to the LNP (23 LNP, 28 ONP) shifts the MRP’s central projection to a combined total of 75 seats (21 LNP, 54 ONP), one short of a parliamentary majority.

If the current Coalition and ONP primary votes were inverted, with One Nation on 21% and the Coalition on 30%, the model projects the Coalition would win 78 seats, enough for a parliamentary majority, with One Nation claiming 11 and Labor reduced to 53 seats.”

That compares to the 43 seats the Coalition won in 2025 with a primary of 31.82%.

“The rise of One Nation as a third force has added a greater level of volatility and unpredictability to the voting landscape. Relatively modest swings between now and the next election could dramatically shift the result,” Mr Hasanakos said.

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