The coalition could be reduced to a regional remnant and Labor seats will come under threat if One Nation builds on its breakthrough by-election victory, analysts say.
David Farley will head to Canberra after the One Nation candidate scored a thumping victory in the southern NSW seat of Farrer on Saturday.
His win over community independent Michelle Milthorpe snapped 77 years of coalition rule in the electorate and marked the first time his party had won a federal lower house seat.
One Nation leader Pauline Hanson and MP Barnaby Joyce have since flagged ambition to add to their lower house total, including in urban areas such as western Sydney.
The result could be replicated in certain outer suburban seats, not just regional ones, former Labor strategist turned leading pollster Kos Samaras said.
“Seats like Lindsay (in Sydney’s west), I could see that seat could definitely become an interesting contest,” the RedBridge director told AAP.
With the Nationals allowed to run in Farrer due to Sussan Ley vacating the seat after her ousting as party leader, the Liberals’ primary vote tanked to 12.4 per cent – down more than 30 percentage points.
Mr Farley dominated outside the regional centre of Albury, where Ms Milthorpe secured the most votes.
The Liberals face the prospect of being pushed completely out of urban seats and being reduced to a rump in the regions, Mr Samaras said.
“I would say that every regional electorate that the Nats and the Liberal party hold is on the block,” he said.
“If you’re getting close to 40 per cent primary vote in Farrer, then it’s going to be a lot higher in inland electorates right across the country.”
Labor was less vulnerable to a similar reckoning, with Mr Samaras pointing out Pauline Hanson’s approval rating was minus 57 with its voters.
“It doesn’t mean Labor doesn’t have a problem,” he said.
“It will lose maybe one or two seats to One Nation.
“Seats like Hunter … that will be a threat, but it is much easier for Labor to combat One Nation because they are the contrast.”
Election analyst Ben Raue suggested it was too early to gauge how much damage One Nation could do in suburban seats, noting the next federal election was a long way off.
“Right now, if we were to have a federal election, One Nation would do quite well and win a bunch of seats,” he said.
“I don’t think this (by-election) tells us that they’re going to sweep the cities. They didn’t win Albury.”
With the coalition tacking to the right to appease defectors to One Nation, Treasurer Jim Chalmers said Labor was the last party standing in the “sensible centre”.
Shadow treasurer Tim Wilson did not shut the door on the coalition partnering with One Nation to form a minority government to defeat Labor at the next election.