Sarah Palin's husband has called a book critical of his family "disgusting lies, innuendo and smears".
The former Alaska governor's camp is seeking to discredit a racy biography that includes allegations of infidelity and drug use.
Todd Palin says author Joe McGinniss has stalked the Palin family in Alaska and is obsessed with his wife.
Mrs Palin's allies also released another denial, from the man alleged to have carried on an affair with the former Alaska governor.
Mr McGinniss said he reported the most accurate story he could, given that Mrs Palin told her friends not to co-operate with his book.
Mrs Palin, the Republican Party's 2008 vice presidential nominee, is considering a White House 2012 bid.