Jim Wilson/The New York Times

From New Hampshire Reporting on the candidates and voters from the Granite State.

ROCHESTER, N.H. — Mitt Romney told a New Hampshire crowd on Sunday afternoon that he knew what it was like to fear a pink slip — but so far, his campaign has not been able to provide any examples of a time when Mr. Romney, the former governor of Massachusetts who spent more than two decades in the private sector, truly feared for his job.

“I know what it’s like to worry whether you’re going to get fired,” Mr. Romney said. “There were a couple of times I wondered whether I was going to get a pink slip.”

On the heels of two debates less than 24 hours apart, Mr. Romney took to the trail Sunday and sought to cast himself as just another regular guy who somehow found himself running for the presidency for the second time in as many cycles.

“I have to tell you: This chance to run for President of the United States, I never imagined I’d do it,” he said. “This is just a very strange and unusual thing to be in the middle of.”

He added: “I mean, I was just a high school kid like everybody else with skinny legs. And, you know, I imagined that I’d be, you know, in business all my career. And somehow I backed into the chance to do this.”

In a debate Sunday morning, Newt Gingrich accused Mr. Romney of “pious baloney” when Mr. Romney — who has sought public office four times since his first failed bid, in 1994, against Edward M. Kennedy for a Massachusetts Senate seat — claimed not to be a career politician. Mr. Gingrich is poised to intensify his criticism of Mr. Romney, including a scathing attack of Mr. Romney’s time at Bain Capital, which his “super PAC” plans to unleash in South Carolina.

The pro-Gingrich PAC bought a 30-minute film that, using Mr. Romney’s career at Bain Capital, casts him as a greedy titan who saw his own wealth rise as companies that Bain acquired were forced to lay off workers and close factories. The PAC also accuses Mr. Romney of not being a true conservative, and of being unable to beat President Obama in November.

Mr. Romney, flanked by three of his five sons and five of his 16 grandchildren, seemed to offer an early rebuttal for the onslaught of attacks he knows are coming when he heads to South Carolina on Wednesday.

“For a while I worked in what’s called venture capital — what is that?” he told the crowd, trying to demystify an industry that still seems to be a foreign concept to many Americans. “Well, we got money from other people and we would use that to help start businesses or sometimes acquire businesses that were in trouble or not doing so well and then try and make it better or get the businesses to grow. And, and when you have other people’s money and your own invested in something, you’re very careful with it.”

Mr. Romney talked about Staples, the office-supply store that Bain first invested in that now has 90,000 employees, explaining: “We opened the very first store. I was there the night we opened the first store. We helped stock the shelves.”

Contrasting himself to the government, Mr. Romney recalled a lean and efficient operation: their office (“in the back of an old, empty shopping mall”), their thrifty chairs (“Naugahyde”), and their board table (“an old table”).

“Because it was the private sector and we were pulling ourselves up in some respects by our bootstraps, we were careful,” he explained.