CONVINCING THE CROTCHETY:

[I]n New Hampshire, the very nature of Scott Brown's self is under siege. And on some level, it must bother him that, having been so achingly and unusually honest about the trials of his life, the biggest issue now facing him is his sincerity, his authenticity as a person.

Like many politicians--Bill Clinton and Barack Obama to name just two--Brown finds power in the personal. The tale of his triumph over poverty, indifferent parents, sexual predators, and bullying stepfathers is so potent that Brown published a searing memoir during his time in the Senate that pulled few punches. (One passage describes how he was tempted to buy the former home of his abusive stepfather just so he could burn it to the ground.) And as he showed at the Holiday Inn, he does not shy away from talking about it.

But running for the Senate in New Hampshire, Brown has had to reconcile his straight-talking, confessional, working-class persona with accusations that he is an opportunist so desperate to get back to the cosseted world of Washington that he pulled up stakes and moved across the state line. A conservative protester at the Concord event conveyed a typical sentiment, standing across the street holding a sign that read "Brownbagger Go Home."

Brown has sought to repel this line of attack by relating the role New Hampshire played in his childhood drama. He was born in Portsmouth and spent his summers in the coastal town of Rye with his grandparents--a refuge, he calls it, from the tumult of his time with his mother, which included living in 17 homes before Brown was 18 and vicious beatings from her and two stepfathers. "When I was going through my struggles, I could spend my summers in Rye," Brown likes to say. Supporters believe he's neutralizing the issue. "He was born here--his family goes back to the 1600s," says Joe Maloy, who owns a printing business in Hooksett that Brown recently toured.

Beyond that, Brown seems determined to defuse the carpetbagger issue the only way he knows how: by getting in that pickup truck and working as many rooms and rope lines as he can. "I have been surprised by how much retail he has been doing," says Fergus Cullen, a former chairman of the state GOP. "I'll go as far as to say he must need it."

Small rooms fit Brown best. He's not a born orator--and he doesn't come preloaded with talk-radio software, like Ted Cruz or Marco Rubio. Neither is he into pledges and promises. (He wouldn't sign one at the gun meeting.) He operates, as someone here told me, like he always has--as a person who lives by his wits, minute by minute, never thinking too far ahead. The skills that saved him as a boy.

It's the same way he won the special election in Massachusetts in 2010. When I covered that race, the moment I realized Brown would win came when I overheard union members coming from a rally for Brown's opponent, Martha Coakley, saying that they were, in secret, going to vote for Brown instead. He had that kind of blue-collar appeal.

This is another state and another time, but Brown is certainly trying--as with the gun group in Concord. His campaign was worried enough about the event to demand that no tape recorders or video cameras be present. But by the end of the meeting, some in the crowd had given Brown credit for at least showing up and hearing them out.

Even as he fights to once again persuade voters of his authenticity, Brown also faces a tricky ideological balancing act. First, he has to win the September primary--although he appears to have a clear edge there. Smith, who served two terms in the Senate, is largely discredited because of his flirtation in the late 1990s with what was then known as the U.S. Taxpayers Party and a subsequent move to Florida, where he again ran for the Senate. Plus, right after Memorial Day, the state's popular Republican senator, Kelly Ayotte, endorsed Brown. A May poll taken by Vox Populi, a new GOP polling firm, showed Brown leading Smith by 25 percentage points.

But once he gets to the general election, he'll need to persuade the electorate to dump Jeanne Shaheen, and in that race, he's an underdog. The same GOP poll had Brown down 12 points to Shaheen; other polls have put the margin at 5 or 6 points. "I think it will take a good wave to take out Shaheen, and I don't see it yet," says Dante Scala, an expert on state politics at the University of New Hampshire.

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