The Pauline Hanson-led party is claiming to have raised more than $3 million from almost 50,000 donors to its anti-Labor "fire the liar" campaign.
Prime Minister Anthony Albanese and other Labor figures have cast doubt on the legitimacy of the fundraising drive, prompting Senator Hanson to share an "independent audit" document authored by a software engineer to her social media page.
Former federal treasurer Wayne Swan labelled One Nation the "billionaire's party", highlighting its links to Australia's richest person Gina Rinehart who in April gifted Senator Hanson a $1 million plane.
"When it comes to big money in this country, it's all going to One Nation," Labor's national president told Nine's Today on Friday.
"This whole debate is a smokescreen for the fact that they are actually run by the top end of town, and they deliver the policies for the top end ... and wage suppression for the rest."
Mr Swan said Labor was fully in favour of disclosure, and the ALP's fundraising efforts wouldn't garner $2 million, as most recently claimed by the right-wing party.
"I doubt very much whether One Nation would raise $2 million either," he said.
Mr Albanese on Thursday questioned what evidence there was that One Nation had actually raised the funds.
"What evidence is there? It is an example of slogans being put forward, not substance," the prime minister told reporters in Sydney.
One Nation senator Sean Bell said Mr Albanese was in denial.
"We were quite excited when he said that because we knew that around the country there (were) tens of thousands of people who had donated, looking at the receipts in their hand and going, this is definitely real," he told Sky News.
"People who've donated are real, and they're mad, they're mad at a bad prime minister because they've seen their standard of living collapse."
Consistent polling is showing booming support for One Nation, which is now the party with the highest primary vote.
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