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A look at Obama's immigration plan. Plus, how long Takata knew of problems with its airbags.
"Double Down" co-author John Heilemann will be on CNN's "The Lead with Jake Tapper" Tuesday. Watch CNN at 4 p.m. ET.
(CNN) - There are a truck load of juicy nuggets in "Double Down," the new book about the 2012 presidential election by Mark Halperin and John Heilemann, the authors of "Game Change."
But one of the most interesting subtexts of the book has not yet received much notice - and that is the motivations of the sources for the book, the folks in the Obama and Romney worlds who dished and dissed.
When Mitt Romney was looking for a running mate, according to the book, his top aide Stuart Stevens was bullish on Governor Chris Christie. Romney ultimately went with Congressman Paul Ryan, but he continues to talk up the New Jersey governor, praising him Sunday on NBC's "Meet the Press."
"Chris Christie stands out as one of the very strongest lights in the Republican Party," Romney said.
But "Double Down" makes it clear that there were a number of Romney aides who came to resent Christie, both because of the way he worked with President Barack Obama after Superstorm Sandy, but also for other reasons. Stunningly, one of them leaked to the authors personal and private vetting information they acquired while considering Christie for the number two slot, including concerns regarding Christie's health and weight, and how Christie had been investigated by the Justice Department for exceeding government travel expense rates.
The leak was a shocking breach of protocol in what is supposed to be a very discreet process.
"I have a great relationship with the Romneys and the campaign, and it's all, its all just you know, trying to make sure they sell as many books as possible," Christie told reporters Friday.
These are the kinds of details that most surprised the political world - not whatever outstanding follow-up questions that the Romney vetters may have had, but the fact that they would serve up those concerns as dish.
Perhaps even more surprising was the amount of leaks from the Obama administration that portray senior Democrats - including the president - in an unfavorable light.
When the authors' first book, "Game Change," came out, lost in all the drama about the Mccain-Palin campaign was the fact that the Obama team did not dish much.
This time, when it came to leaks the White House was a veritable colander.
Obama is depicted struggling rather sadly with debate prep, as his advisers are depicted losing their patience with him. "I just don't know if I can do this," Obama says at one point.
On ABC's "This Week" Sunday, George Stephanopoulos seemed stunned that the president wasn't upset at the amount leaked about him by his trusted aides, saying to White House senior adviser Dan Pfeiffer, "I can only imagine what he's thinking as he sees all of these details in the book?"
"We are not the first White House to deal with leaks. Every White House has dealt with it. I think we have been more leak-free than most. And where we find them we try to stop them," Pfeiffer responded.
"The president is always frustrated about leaks," Pfeiffer said. "I think anyone who leaks has to pay the price. I don't know who leaked in that book."
Other senior Democrats embarrassed include Vice President Joe Biden. The book reveals that the team explored replacing him with Hillary Clinton, though the Obama administration denies it.
"I know for a fact that President Obama never considered this, never thought about it, never entertained it," White House Press Secretary Jay Carney said Friday.
In another scene Obama, after golfing with former President Bill Clinton, says to an aide, "I like him ... in doses."