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DES MOINES, Iowa (AP) – As Mitt Romney closes in on a decision about whether to again run for president, he does so without several major donors who supported him in the past and a veteran Iowa staffer — defections all to former Florida Gov. Jeb Bush.

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The donors, in interviews with The Associated Press, said they see in Bush what they liked about Romney in 2012, the capacity to serve successfully as president, but also something Romney could not muster over two campaigns: the personality and senior staff needed to win the White House.

“I’ve got great respect for Gov. Romney, and I busted my buns for him,” said Chicago investor Craig Duchossois, whose wife contributed $250,000 to a pro-Romney super PAC while he collected tens of thousands more for Romney’s last campaign. “But I have turned the page.”

Beyond the donors, Romney lost one of his most trusted political advisers on Thursday when David Kochel joined Bush’s team. Kochel, who led Romney’s campaign in Iowa in 2008 and 2012, is in line to play a senior role in Bush’s campaign should he run, Bush spokesman Kristy Campbell said.

Romney’s inner circle was surprised to lose Kochel, whom Campbell called one of “the most respected strategists” in the country.

The defections to Bush do not, as of yet, appear so definitive as to keep Romney from the race.

There are many free agents among the major GOP donors, each with the ability to contribute personally and collect from others the hundreds of millions needed to run a modern presidential campaign.

Several veterans of GOP politics also told the AP this week they feel that all of the major candidates — Romney, Bush, New Jersey Gov. Chris Christie, Florida Sen. Marco Rubio and Wisconsin Gov. Scott Walker among them — would be able to raise the money needed to compete in a GOP primary campaign that may feature as many as two dozen contenders.

But hesitation from some Romney loyalists and outright defection by others will make his path to the nomination a greater challenge than it was four years ago, when he was viewed as the front-runner from the campaign’s outset.

“I think it’s becoming exceedingly difficult,” said Gordon D. Sondland, a member of Romney’s national 2012 finance team who is now solidly behind Bush.

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The undecideds include New York Jets owner Woody Johnson, who was among Romney’s most powerful and vocal national fundraisers. One of Romney’s biggest bundlers from 2012, New York-based investment banker Patrick Durkin, is solidly behind Bush, having already hosted a fundraiser for him in Greenwich, Connecticut.

Duchossois and several fellow top Chicago-area Romney supporters met privately with Bush in Chicago in December. After a quick chat about a potential campaign plan, Bush sat for more than an hour of questions. Most, though not all, of the roughly 20 at the meeting walked away Bush supporters.

“It cut the deal for me,” Duchossois said.

He is among the donors who will host Bush at a Feb. 18 fundraiser arranged by Lisa Wagner, Romney’s 2012 Midwest campaign finance director, who helped raise $25 million for Romney in 2012.

Bush also has claimed Romney’s 2012 Texas finance director, Allison McIntosh, and Sondland, who helped raise millions for Romney and the super PAC that supported his candidacy.

“A lot of these folks had already committed to Gov. Bush and aren’t going to change their loyalty midstream,” said Sondland, a Portland, Oregon, hotelier.

Several of Romney’s backers in the Chicago-area said they respected Romney’s worldview and policy positions but are discouraged that he appears to be taking advice from the same cadre of advisers who led his previous campaigns.

“Jeb represents the different traits, that are qualifications to hold the office and those required to be elected,” said Terry Graunke, co-founder of a Chicago private equity firm. “He and his team appear to be much more capable of contemporary strategic policy.”

Romney has acknowledged privately in recent weeks that he needs to make a decision soon — perhaps within the next two weeks. His aides acknowledge that a third campaign will be more difficult than the second, but insist he will have the necessary financial support, noting his supporters raised more than $1 billion during the 2012 election.

“It’s Romney first, then Jeb,” said Bill Kunkler, a vice president of a Chicago private equity firm whom Romney telephoned this month to discuss the possibility of another run.

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