Romney's personal feuding with Perry, Newt Gingrich and Rick Santorum occupies a large portion of the story, including allegations that the Romney campaign had fostered rumors regarding Gingrich's request for an "open marriage" with his second wife shortly before divorcing her for his mistress, and the revelation that Santorum had brought a stillborn son home for his family to see. The authors write that Romney decided not to choose Chris Christie as his running-mate, in part due unanswered questions through the vetting process about a defamation lawsuit and a Securities and Exchange Commission investigation, as well as his weight. Christie and the Romney campaign later quarreled with each other, including an argument with a Romney adviser at the 2012 Republican National Convention. During the campaign, Harry Reid, the Senate Majority Leader, stated that a Republican source who invested in Bain Capital, Romney's financial services company, informed him that Romney had not paid taxes in ten years. In the book, Heilemann and Halperin attribute this to Jon Huntsman, Sr., who had previously denied being Reid's source. Peter Hamby, writing for "The Washington Post", said "the book lacks the made-for-Hollywood scenes of ""Game Change"", but "there’s still click-bait aplenty". Ezra Klein wrote for Bloomberg that the book "is a joyous romp through the seedy underbelly of presidential campaigning". Michael Kinsley wrote for "The New York Times" that "Double Down" "may be the first political book ever with more excrement than sex". Prominent individuals mentioned in the book have responded publicly about its contents. Discussing the book's claim, Huntsman, Sr. again denied being Reid's source, calling the claim "supermarket tabloid trash." Christie indicated that Romney called him to apologize about the leaks from his campaign. When responding to claims about incomplete vetting reports, he dismissed the criticism as "part of the parlor game of Washington D.C.", and said that "political advice from people who ran the Romney campaign is probably something nobody should really give a darn about". Regarding the possibility of swapping Biden for Clinton as his running mate, Obama told Chuck Todd of NBC News that "if they had asked me, I would have said there is no way that I am not running again with Joe Biden". HBO Films, which produced "Game Change", the film version of the book, optioned the rights to "Double Down". When asked about casting, Halperin suggested Will Smith or Giancarlo Esposito would be his choices for Obama, while George Clooney or Jon Hamm could play Romney.