WASHINGTON — Mitt Romney, the 2012 Republican presidential nominee, told a group of supporters on Friday that he would not seek his party’s nomination for president in 2016.
Mr. Romney, the former Massachusetts governor, shared his decision on a conference call with a small group of advisers.
In a second call to a larger group of supporters, Mr. Romney said, “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.”
Mr. Romney said he believed he could win the nomination, but he expressed concern about harming the party’s chances to retake the White House. “I did not want to make it more difficult for someone else to emerge who may have a better chance of becoming the president,” he said.
He added that it was “unlikely” that he would change his mind.
Mr. Romney, who did not take questions and ended the call shortly after reading a prepared statement, said that his family had been gratified by the outpouring of support, but had decided that it was best for the Republican Party to step aside. Mr. Romney said he would have no leadership PAC and no exploratory committee.
By not pursuing a third White House bid, Mr. Romney frees up scores of donors and operatives who had been awaiting his decision, and creates space for other potential center-right candidates such as former Florida Gov. Jeb Bush.
Mr. Romney, 67, had expressed renewed interest in another presidential run to a group of donors earlier this month, roiling the nascent Republican race. Many of his loyal contributors, staff members and supporters had been reluctant to come out for one of his potential rivals until they knew Mr. Romney’s plans.
But his flirtation had also prompted a fierce backlash across Republican circles, and some of Mr. Romney’s former aides and donors have begun moving on to other candidates.
In a more than four-hour meeting last week, Mr. Romney’s top staff members and trusted advisers from 2012 relayed a sobering reality — they supported Mr. Romney and thought he would be the best president, but they did not necessarily encourage a third run.
One by one, loyal supporters talked about surveying their troops from 2012, and finding that the enthusiasm and support were just not there. Some Iowa precinct leaders were not coming back, and even in New Hampshire — where Mr. Romney had won the primary — the mood was described at best as “cautiously optimistic.” The situation with donors was also going to be an uphill climb.
Word of Mr. Romney’s decision sent waves through the Republican donor world early Friday, as Romney aides began to telegraph the news to donors and other staff members and strategists. Some donors immediately began calling representatives of other potential candidates, such as Gov. Chris Christie of New Jersey, to discuss offering their support.
Mr. Romney’s announcement started a day of reckoning with his would-be rivals. He is scheduled to have dinner with Mr. Christie on Friday evening, according to two people with knowledge of his schedule, suggesting that Mr. Romney may be considering throwing his support, and that of his own political operation, to Mr. Christie. The two men are friendly, and Mr. Christie, along with Mr. Bush, was a main rival of Mr. Romney for the favor of the Republican establishment.
Mr. Bush offered his own warm words for Mr. Romney in a post on Facebook on Friday morning.
Mitt is a patriot and I join many in hoping his days of serving our nation and our party are not over,” Mr. Bush wrote. “I look forward to working with him.”
At 11 on Thursday night, a blast email was sent from a mittromney.com address, alerting supporters about a conference call on Friday morning.
“Please join me for an update call tomorrow at 11:00 a.m. EST, 8:00 a.m. PST,” wrote Mr. Romney, adding the dial-in information and concluding, “All the best, Mitt.”
In an appearance at Mississippi State University on Wednesday, Mr. Romney sounded themes that could have shaped another campaign. But he also lamented the nature of the political process and offered a dose of barely veiled self-criticism, discussing some of the shortcomings of his 2012 campaign and the lessons he learned from his loss to President Obama.
Mr. Romney’s decision will almost certainly bring an end to his decade-long quest to become president. He lost in the Republican primary in 2008 before becoming his party’s standard-bearer four years later.
Friday’s conference call seemed bittersweet for the Romney family. At one point, Mr. Romney’s wife, Ann, came on the line and thanked the former aides for their steadfast support.
But luck was clearly not with Mr. Romney this time, even as he shared the news with his former staff members on his morning call. Mr. Romney’s voice fell off the line as the connection was suddenly dropped.