(CNN) - John McCain's campaign is denying Democratic charges the presumptive Republican nominee flippantly dismissed a new book attacking Barack Obama that includes several documented falsehoods.
Asked by the Associated Press earlier Friday what he though of author Jerome Corsi's new book, "The Obama Nation," McCain said, "gotta keep your sense of humor."
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Those comments were immediately slammed by the Obama campaign and the Democratic National Committee, which e-mailed its 3.4 million supporters declaring, "John McCain thinks smears and lies are funny."
"Despite pledging to run a respectful campaign, McCain is just standing by while Corsi and his publisher, former Dick Cheney aide Mary Matalin, poison this presidential race," read the e-mail from DNC Rapid Response Team.
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But McCain spokeswoman Brooke Buchanan said later Thursday the Arizona senator actually did not hear the question, and would not be commenting on the book.
The book, which is expected to debut No. 1 on the New York Times bestseller list, repeats many long-discredited falsehoods about the Illinois senator, including the claim that he is Muslim.
Corsi, who has said he's on a “mission” to take down Obama, also co-wrote "Unfit for Command" - the 2004 book that spawned the Swift Boat Veterans for Truth attacks against then-Democratic presidential nominee John Kerry.