Republican Mitt Romney will not run for president in 2016

Republican Mitt Romney, after a three-week flirtation with another run for president, said definitively on Friday that he will not seek the White House in 2016.

Romney's decision could be a boost for former Florida Gov. Jeb Bush and New Jersey Gov. Chris Christie, who were competing for the support of the Republican Party's establishment-minded voters and donors. Romney's exit comes after several of his former major donors and a veteran staffer defected to support Bush, the brother and son of former presidents.

"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 told supporters on a conference call.

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.

Romney, who is 67, 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, Romney sounded every bit like a politician preparing to run for president.

Obama is barred from a third term, and Hillary Rodham Clinton is the presumed Democratic frontrunner. The Republican race remains wide open.

The exit of Romney from the campaign most immediately benefits the other favorites of the party's establishment wing, including Bush, 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, who is popular with libertarians, Texas Sen. Ted Cruz, a champion of the anti-tax tea party movement, and former Arkansas Gov. Mike Huckabee, who has support among evangelical Christians.

Romney's aides had acknowledged a third campaign would have been more difficult than his second, but insisted he would have had the necessary financial support, noting his supporters raised more than $1 billion during the 2012 election.

If he would've run, Romney would have been attempting something not achieved in American politics since the 1968 election of Richard Nixon: a presidential nominee who lost a general election and then came back to win. Nixon, who lost to John F. Kennedy in 1960, also remains the last nominee to lose as a major party's standard-bearer and then win nomination again. Such a feat had been common before the modern voter-driven nominating system of primaries and caucuses came into being.

Romney's decision against running clearly pained him, and he took no questions from supporters on Friday's call.

In his call with supporters, Romney appeared to take a swipe at Bush, saying it was time for fresh leadership within the Republican party.

"I believe that one of our next generation of Republican leaders, one who may not be as well-known as I am today, one who has not yet taken their message across the country, one who is just getting started, may well emerge as being better able to defeat the Democrat nominee," Romney said. "In fact, I expect and hope that to be the case."