The Republican Party's 2012 nominee plans to tell supporters about his plans to pass on another national campaign during a conference call. He first let his staff know in a separate call that he was out of the race.
"After putting considerable thought into making another run for president, I've decided it is best to give other leaders in the party the opportunity to become our next nominee," Romney said in a statement, which he planned to read to supporters on the call.
The former governor of Massachusetts had jumped back into the presidential discussion on Jan. 10, when he surprised a small group of former donors at a meeting in New York by telling them he was eyeing a third run for the White House.
It was a monumental change for Romney, who since losing the 2012 election to President Barack Obama had repeatedly told all who asked that his career in politics was over and that he would not again run for president.
In the days since that meeting in New York, which caught several in attendance off-guard, Romney made calls to former fundraisers, staff and supporters, and gave three public speeches in which he outlined his potential vision for another campaign.
"I'm thinking about how I can help the country," he told hundreds of students Wednesday night at Mississippi State University.
In that speech, and what amounted to a campaign stop a few hours before at a barbeque restaurant with Mississippi State's football coach Dan Mullen in tow, Romney sounded every bit like a politician preparing to run for president.
"We need to restore opportunity, particularly for the middle class," Romney said. "You deserve a job that can repay all you've spent and borrowed to go to college."
But as Romney sounded out his former team about putting together a new national campaign, he discovered that several of his past fundraisers had already made plans for 2016 and were committed to supporting former Florida Gov. Jeb Bush.
Several key former Romney donors told The Associated Press this week that in Bush they see someone who can successfully serve as president, as they believe Romney could. But they also think Bush has the personality and senior staff needed to win the White House, something the former Massachusetts governor could not bring together in his two previous presidential campaigns.
"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."
Romney also 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 now line to play a senior role in Bush's campaign should he run.
Romney's inner circle was surprised to lose Kochel, whom a Bush spokesman called one of "the most respected strategists" in the country.
The exit of Romney from the campaign most immediately benefits the other favorites of the party's establishment wing, including Bush, New Jersey Gov. Chris Christie, Florida Sen. Marco Rubio and Wisconsin Gov. Scott Walker.
The more conservative side of the field is largely unchanged, with a group of candidates that will likely include Kentucky Sen. Rand Paul, Texas Sen. Ted Cruz, former neurosurgeon Ben Carson and former Arkansas Gov. Mike Huckabee.
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