Left-leaning millennial and gen Z voters are expected to be less likely to swing to the political right as they age than earlier generations, demonstrating an emerging challenge for the Liberal and National parties.
The Centre for Independent Studies has released research on intergenerational voting patterns and potential impacts on the electorate.
Data collected from previous elections showed voters born before 1981 tended to swing to the right as they aged.
At the 2022 federal election, the oldest baby boomers - people born between 1946 and 1964 - were 15.2 percentage points more likely to vote for the LNP.
The oldest gen Xers - born before 1981 - were 2.2 percentage points more likely to vote for the coalition, following the voting trajectory of Boomers at the same age.
But millennials not only entered the electorate with lower levels of support for the coalition than previous generations, they also had less inclination to vote for the LNP as they entered their 40s.
Report author Matthew Taylor said it was unlikely millennials would follow the pattern of earlier generations and reach a level of support for the coalition in their early 50s.
Based on current trends, he said this would not happen until millennials reach their 80s.
"Generation Z entered the electorate with the lowest support for the coalition of any post-war generation," he said.
"As they approach their 30s, their support for the coalition is not increasing it is falling even further."
At the next election, generations born after 1980 will make up nearly 49 per cent of the electorate.
By 2040, they will make up just under 70 per cent.
The report demonstrates how generational change could impact the electoral fortunes of the LNP.
The coalition would need large increases to its primary vote from people born before 1996 in order to return to power.
Even an increasing share of the vote from the decreasing Boomers and generation Xers within the electorate would be insufficient to return the coalition to power in the medium term, the report predicted.
Mr Taylor said future policies would be different if shaped by a centre-left government being held to account by a far-left opposition than by one on the centre-right.
"There is a narrow path back to government for the coalition in the medium term," he said.
"That road goes through millennials and generation Z, not around them."
