Mrs Palin's book is already at the top of the bestsellers lists
Former US vice-presidential candidate Sarah Palin has described deep tensions during the Republican campaign and claimed she was left with a vast bill.
Her autobiography, already at the top of some bestseller lists on advanced sales, is to be published on Tuesday.
In the memoir, entitled "Going Rogue", she says she was left to pay fees of $50,000 to be vetted for the position.
But an official from John McCain's campaign is reported as saying such accusations were "false".
"To my knowledge, the campaign never billed Gov Palin for any legal expenses related to her vetting," Trevor Potter said, according to the Associated Press.
In the book, Mrs Palin says she was not aware that she would have to personally cover the expenses - which she says come to $50,000 (£30,000) - if the Republican campaign lost.
She also describes being prevented from speaking to reporters and being blocked from giving a concession speech on the night of the election.
The book, which had an initial print run of 1.5 million copies, has reportedly already earned Mrs Palin an advance of $1.25m (£740,000).
Mrs Palin shot to fame as Senator McCain's Republican running mate in the presidential election of November 2008, becoming a lightning rod for praise and criticism alike.
In the book, she also complains about being forced to undergo a makeover, including wearing expensive clothes.
During the campaign, when it emerged that the Republican National Committee had reportedly spent some $150,000 on new clothes for her and her family in the first two months of the campaign, it sparked a scandal.
In the book, she asks herself if she and her family came across as "that" unpresentable.
She also writes about the personal turmoil of her teenage daughter's pregnancy unfolding in the glare of the media spotlight.
But there is no reference to the father of her grandson, Levi Johnston, who has reportedly threatened to reveal secrets that will "hurt her" unless she leaves him alone.
She also says that she only agreed to giving a much-criticised interview with CBS television presenter Katie Couric because she was told the journalist had low self-esteem.
But she describes the tone of the encounter, which dented her reputation, as "badgering", condescending and biased, alleging that her strongest answers were edited out of the broadcast interview.