The book, the sequel to the pair's insider look at the 2008 campaign that goes on sale Tuesday, paints Huntsman's unsuccessful campaign as a mess from the start: drowning in debt, scarred from infighting and led by a candidate unwilling to take the hard jabs needed to draw attention.
"As autumn unfolded," the book's authors write, "Huntsman's advisers finally, fully came to dismiss their candidate as a lazy, whiny wuss. Huntsman came to disdain his adjutants as soulless mercenaries."
The book zeroes in on Huntsman's biggest problem: money.
Advisers had assumed and counted on big help from the Huntsman clan, especially the candidate's dad, billionaire Jon Huntsman Sr., but the promises fizzled and the younger Huntsman ordered his campaign to turn down his father's money.
The candidate himself was sickened by his advisers' insistence that he loan the campaign a total of $7 million as fundraising dried up.
"I am not going to mortgage my family's future for this presidential race," Huntsman reportedly said, according to the book.
The candidate eventually put $5.1 million into his failed bid to close out leftover bills, while his father donated more than $2 million to a super political action committee that backed Huntsman for president.
The Huntsman camp disputed the book's premise with regards to the ex-governor's campaign.
Abby Huntsman, the candidate's daughter and now a host of MSNBC's "The Cycle," took aim at the reporting in the book during her show Monday.
"With every failed campaign, you expect a fair share of criticism, but, with this book, everyone walked out of their respective campaign headquarters and turned on the fire hose," she said. "It's filled with leaks about other leaks. It reminds me more of high school gossip than actual serious investigative reporting. My family expected to be picked apart but as someone who was actually there every step of the way, there was very little worth even responding to [in the book], very little based in reality, most based in conjecture, perception and self-promotion."
The idea of Huntsman as an independent candidate had been kicked around a good deal during his bid, especially with his ties to Americans Elect, a group pushing to get a ballot spot in every state in the nation. Huntsman's supporters in New York had urged the candidate to drop the GOP effort and go it alone, according to the book.
Huntsman met with New York Mayor Michael Bloomberg over dinner near Columbus Circle and asked about the idea; the billionaire mayor quickly dismissed such a move as "formidable," but added that Huntsman was the perfect embodiment of an independent candidate, the book says.
Huntsman later dropped the plan of leaving the Republican race, deciding that it would be better to try and change his lifelong party from the inside rather than from the outside.
More details to emerge from "Double Down:"
• Though Huntsman's personal wealth has been estimated at or near $70 million, the new book says that the candidate's net worth was more like $11 million, including his real-estate holdings. Huntsman balked at asking his billionaire dad for an unsecured loan. "My father is not going to be involved in this," he said. "I'm doing it on my own."
• The book also claims that Huntsman's presidential campaign was behind two of the more famous leaks in the 2012 White House race, ones that led to the ouster of former Godfather Pizza CEO Herman Cain at the height of his popularity and pre-empting a bid by then-Indiana Gov. Mitch Daniels.
• In an attempt to air their own dirty laundry before his official announcement, the Huntsman folks leaked a letter the ex-Utah governor had written to President Barack Obama calling him a "remarkable leader." The Huntsman camp had denied it was the source but in fact, had discovered the letter in Huntsman's gubernatorial archive and handed it to the conservative Daily Caller.