CONCORD, N.H. (AP) — Republican presidential candidate Jon Huntsman wants to go head to head with Mitt Romney in the former Massachusetts governor’s own backyard.

With a laser focus on New Hampshire, President Barack Obama’s former ambassador to China is quietly assembling what may end up being the largest paid GOP primary effort in the state’s history. He’s also taking a sharper tone as he fights to overcome a staff shakeup and low popularity among the relatively few Republican voters who know him.

“I’m running on my record,” Huntsman told a Dartmouth College audience Tuesday. “A lot of people run from their record.”

The comment was a subtle jab at Romney, whose job-creation record as governor is coming under scrutiny as he leads some early polls. Huntsman also criticized his former boss, Obama.

“The president’s a good man. He’s got a good family. He’s earnest,” he said. “But he’s fundamentally failed us on the most important issue of our time.”

That’s a message Granite State voters should get used to hearing as the first-in-the-nation primary state becomes the priority in Huntsman’s uphill battle to capture the 2012 nomination. Tuesday visit was Huntsman’s second this month. And he plans to return for the first week in August.

The former Utah governor, whose record features some moderate positions on issues the GOP’s conservative base cares about deeply, has said he won’t compete in the Iowa caucuses that kick off the voting early next year. However, Huntsman’s campaign is careful not to overplay expectations in New Hampshire, a state where Romney enjoys near-unanimous name recognition and has a summer home on Lake Winnipesaukee. Romney leads the GOP field in statewide and national polls as well as in fundraising, with $18 million raised in the first few months of his campaign.

Conversely, recent polling suggests that a significant bloc of likely GOP primary voters in New Hampshire and elsewhere do not know Huntsman. And some who do — nearly 20 percent in a recent Suffolk University poll in New Hampshire — have an unfavorable view of him. He was the first choice of just 4 percent of respondents in the late June survey.

When pressed this week, Huntsman’s campaign didn’t offer any internal polling to suggest his standing is stronger. He’s raised roughly $4 million, with about half of it coming from his personal wealth.

“Although he’s got some staff presence, I’m not seeing any opinion leaders in New Hampshire circling around his campaign and committing to it,” said New Hampshire conservative leader Ovide Lamontagne, who has yet to endorse in the presidential contest. “It seems like there’s a lot of groundwork being laid, but not a lot of progress, at least not publicly.”

Huntsman opened a Manchester headquarters in early July, and state director Ethan Eilon said plans call for offices in Concord, Nashua and the populous seacoast region by the end of August. Three or four more offices are expected to open by the end of September in this state of 1.3 million people.

The candidate added two New Hampshire employees this week, bringing to 21 the size of his paid staff in the state. That’s almost triple the size of any other presidential contender, including Romney.

If the campaign follows through with its plans, “it would be the biggest paid operation for a Republican campaign in New Hampshire primary history,” said Jamie Burnett, a political veteran who was Romney’s state political director in 2008. “It also underscores the fact that Huntsman, like Romney, must win New Hampshire in order to compete successfully in later contests.”

Huntsman’s team says the nascent operation needs time to take hold, and upcoming visits will help Huntsman improve his standing.

At least one person was disappointed after Tuesday’s address that Huntsman spoke only to the audience from the stage and left immediately afterward.

“Usually candidates are more generous with their time,” said Pete MacDonald. “It’s a big mistake. He’s brand new.”

Huntsman’s New Hampshire strategy comes on the heels of internal campaign upheaval that raised fresh questions about Huntsman’s prospects in a crowded GOP field. His campaign manager, Susie Wiles, resigned last week only a month after Huntsman entered the race. Matt David, his communications director, took over and aides signaled that Huntsman would more aggressively go after his opponents, Romney in particular, although he pledged earlier to run a civil campaign.

The new aggression has already surfaced in rhetoric from aides in recent days, and the candidate himself criticized Romney in an email to reporters Monday titled “The Romney-Obama budget plan: Raise Taxes.”

While Huntsman did not assail Romney by name at Dartmouth, aides say that doesn’t suggest that Huntsman is shying away from contrasting himself with his rivals, and one in particular.

“He’s said numerous times that he’s running on his record, not away from his record. Some other candidates — Mitt Romney — are running away from their record,” New Hampshire spokesman Michael Levoff said before the Dartmouth event. “We’re going to communicate that message.”

Romney’s team, for now at least, declined to take the bait.