HUDSON, New Hampshire (Reuters) - Republican Mitt Romney was back on familiar turf in New Hampshire on Sunday, looking to steady his White House campaign after a potentially damaging gaffe over a wager he offered at a candidate's debate in Iowa.

Speaking to reporters after a town hall meeting, Romney made light of the incident on Saturday when he offered to bet Texas Governor Rick Perry $10,000 over what Romney wrote in his book about Massachusetts' controversial healthcare law that he helped engineer as governor.

Perry did not take the bait. But Republicans and Democrats alike jumped on Romney, painting the multimillionaire former venture capitalist as out of touch with the concerns of regular Americans.

"After the debate was over, (wife) Ann came up and gave me a kiss. She said I did great, but that 'betting is not one of my strengths,'" Romney said.

The former Massachusetts governor said he was confident of his standing in the Republican primary field, even though former U.S. House of Representatives Speaker Newt Gingrich has soared to the top of opinion polls nationally and in early primary voting states like Iowa and South Carolina.

Romney still holds a solid lead in New Hampshire, where he owns a vacation home, but has lost ground over the past month to Gingrich.

"It's very fluid. These polls have bounced all over the place in the past year," Romney said.

"I think I will become the nominee," he said, adding the primary process "could go on and on and on" before a winner is declared. "We are prepared to go on a nice, long and highly successful campaign," he said.

Romney and his fellow candidates will be back in Iowa for another debate on Thursday hosted by the Iowa Republican Party. The state kicks off the state-by-state Republican nominating process to pick the party's candidate to challenge President Barack Obama in the November 2012 election.

One of Romney's co-chairs in the Midwest state, attorney Brian Kennedy, said he was not worried by Romney's debate misstep.

"Jobs and the economy, those are the issues that are going to drive the election," Kennedy said. "When the focus has been there, Mitt Romney's done quite well."

In Sunday's town hall meeting, Romney made a rare campaign trail reference to his Mormon religion, telling a lengthy anecdote about how his missionary work in France in the late 1960s helped shape his worldview.

The usually buttoned-down candidate, who "grew up in a home with a great deal of affluence," described using outside squat toilets and paying "a few francs" to use a public shower once a week while living on a shoestring.

"Most of the apartment I lived in had no refrigerators, no showers. No bathtubs," Romney said.

"I became much more serious about my life," he said. "I came home looking forward to getting an education so I could lift my family."