Mitt Romney began his retreat from public life Wednesday at a private breakfast gathering with a couple hundred of his most loyal and affluent campaign benefactors. The former Massachusetts governor, humbled by the thumping that ended his six-year pursuit of the presidency, reminisced about the journey and tried not to cry.

Romney waxed about the roaring crowds in the campaign’s closing days and the feeling that he was winning, said donors in attendance. He commended Stuart Stevens, his chief strategist, as well as his senior aides, and then went around thanking donors one by one.

“Mitt was vintage Mitt,” said L.E. Simmons, an oil investor on Romney’s national finance committee. “He was analytical, no notes, spoke from the heart and was very appreciative.”

But Romney’s top aides, who only a couple of days ago were openly speculating about who would fill which jobs in a Romney administration, woke up Wednesday to face brutal recriminations.

Some top donors privately unloaded on Romney’s senior staff, describing it as a junior varsity operation that failed to adequately insulate and defend Romney through a summer of relentless attacks from the Obama campaign over his business career and personal wealth.

“Everybody feels like they were a bunch of well-meaning folks who were, to use a phrase that Governor Romney coined to describe his opponent, way in over their heads,” said one member of the campaign’s national finance committee, who requested anonymity to speak candidly.

“Romney World,” the fundraiser added, “will fade into the obscurity of a lot of losing campaigns.”

Stuart Stevens, who as Romney’s chief strategist was the recipient of some of the harshest blame, did not return requests for comment Wednesday. Nor did many of Romney’s other top advisers, who during Romney’s concession speech were visibly shell-shocked.

Bob White, Romney’s close friend and business partner who chaired the campaign, strongly defended Stevens and the rest of the staff in an interview a few weeks ago.

“Mitt never doubted his team, and the reports of infighting were not true,” White said.

In Washington, meanwhile, scores of transition-team staffers who had been preparing for a Romney administration started packing their belongings Wednesday.

Mike Leavitt, the former Utah governor running the transition, convened a conference call at 10 a.m. to inform the staff they had until Friday to organize their files, return their laptops and cellphones and vacate their government office.

At the Wednesday breakfast, Romney told the donors he believed Hurricane Sandy stunted his momentum in the final week of the campaign, according to multiple donors present.

Although Romney himself stopped short of placing any blame on New Jersey Gov. Chris Christie, who praised President Obama’s leadership during the storm, several Romney supporters privately pointed fingers at the outspoken governor.

“A lot of people feel like Christie hurt, that we definitely lost four or five points between the storm and Chris Christie giving Obama a chance to be bigger than life,” said one of Romney’s biggest fundraisers, who requested anonymity to speak candidly.

Another major Romney fundraiser said Christie’s embrace of Obama after Sandy walloped his state only deepened a rift that opened between the Romney and Christie camps over the summer.

Christie and his wife were unhappy with Romney’s vice presidential search process, believing they were “led a little bit far down the garden path” without being picked, the fundraiser said.

Romney advisers have said they were disappointed with Christie’s keynote address at the Republican National Convention because they believed the speaker focused too much on himself and not enough on the candidate. Republicans close to Christie, however, said the Romney team approved the final draft of the speech.

Some Romney advisers insisted Wednesday that tensions with Christie have been overstated.

“The problem with Sandy was not Chris Christie,” said one political adviser. “The problem with Sandy was we couldn’t talk about the choice argument for the last week of the campaign. At a time when Barack Obama’s campaign was small, it allowed him to be bigger, and provided him a vehicle for him to show he can be bipartisan.”

Christie on Wednesday defended his work as a surrogate on Romney’s behalf, saying, ”I did my job.”

“I wouldn’t call what I did an embrace of Barack Obama,” Christie said at a news conference. “I know that’s become the wording of it, but the fact of the matter is, you know, I’m a guy who tells the truth all the time. And if the president of the United States did something good, I was gonna say he did something good and give him credit for it.”

He continued, “But it doesn’t take away for a minute the fact that I was the first governor to endorse Mitt Romney, that I traveled literally tens of thousands of miles for him, raised tens of millions of dollars for him and worked harder, I think, than any other surrogate in America other than Paul Ryan, who became his running mate.”

The time will come for Romney and his campaign leadership to fully assess what went wrong. Some of his top donors immediately pointed to the campaign’s early strategic decision to frame the race as a referendum on Obama rather than a choice between two different governing philosophies and leadership styles.

A second member of Romney’s national finance committee said that while the campaign’s tactics and fundraising organization were executed well, the strategy and message were “total failures.” This fundraiser added that the campaign’s cautious and adversarial relationship with the news media proved detrimental.

“That strategy was we don’t want to define differences, we want it to be a referendum not a choice, but it was always going to be a choice. Elections are a choice. Their fundamental premise was incorrect — and when you’re incorrect on this level, you are shunned by people in the party,” said the fundraiser, who requested anonymity to speak candidly.

But Romney, those close to him said, is not second guessing the counsel or work of his staff. After he spoke at Wednesday’s breakfast, Simmons said he spoke privately with Romney.

“I said, ‘So what are you going to do for the next few weeks? Let’s do something fun,’ ” Simmons recalled. “And he said, ‘Uh, I’m going to be really busy.’ He said, ‘I have 400 people to get great jobs for.’ ”

Late Wednesday afternoon, as sleet fell in Boston’s North End, Romney visited his campaign headquarters for one final staff meeting. He thanked his aides and said goodbye. His Secret Service detail gone — and with it his code name, Javelin, after a car once made by his father’s company — Romney was spotted driving off in the backseat of his son Tagg’s car. His wife, Ann, was riding shotgun.