Voters will find out next week how the Liberal Party chooses to preference Clive Palmer, after a new poll suggesting he could be kingmaker in key marginal contests.
Prime Minister Scott Morrison has not ruled out a preference deal with Mr Palmer, saying it's ultimately a decision for the party organisation.
"We'll have the discussions as we do with many parties, we'll come to a view," he told reporters in Adelaide on Tuesday.
"But ultimately, at the end of the day Australians will decide who the next prime minister will be."
How-to-vote cards will need to be finalised in time for early voting which starts on April 29.
A Newspoll released on Tuesday shows Mr Palmer's United Australia Party holds between five and 14 per cent of the primary vote in the marginal seats of Herbert (Queensland), Deakin (Victoria), Lindsay (NSW) and Pearce (WA).
"I think what this shows is this election will be close and everybody's vote will matter," Mr Morrison told Sky News.
Opposition Leader Bill Shorten says he won't get distracted by Mr Palmer's possible political comeback.
"There is only one person who has been resurrected and I won't compare Clive Palmer to him," he told reporters in Gladstone in Queensland.
In April 2017, Mr Palmer compared Mr Morrison to Nazi SS chief Heinrich Himmler and the Australian Securities and Investments Commission to the Gestapo over talk of an ASIC probe into his company.
But Mr Morrison dismissed the insult, saying he was looking to the future at the next election.
One Nation will be put below Labor on Liberal how-to-vote cards, after an undercover Al Jazeera story rocked the minor party.
"The Queensland LNP actually held an executive meeting to endorse that position," Mr Morrison said.
Opposition frontbencher Anthony Albanese warned against voting for "fringe" minor parties because MPs often shifted allegiances after being elected.
He said Mr Palmer's previous stint in parliament was a debacle and his attitude towards his workers was "quite outrageous".
Mr Palmer has been heavily criticised for not paying employee entitlements after the collapse of his Queensland nickel refinery in 2016.
Mr Albanese said discussions about preference deals with Mr Palmer were above his pay grade.
The poll conducted for The Australian gives UAP more support than Pauline Hanson's One Nation in the four marginal seats.
"Clive Palmer's put out $31 million in advertising - of course that's going to cut through," she told Nine's Today.
"Clive Palmer is in it for Clive Palmer, not for the Australian people. I hope people see through that."
On a two-party preferred basis, the major parties are neck and neck in Herbert and Pearce, while Labor has a 51-49 lead in Lindsay and the Liberals a 51-49 advantage in Deakin, according to the Newspoll.
The survey of 2191 voters in the four electorates was conducted on Sunday and has a margin of error between 3.9 and 4.3 percentage points.
