Bedford, N.H. — Kelly Ayotte meets me at Panera Bread, which, a campaign aide confides, is one of her favorite spots. Lodged in the corner of a concrete strip mall south of Manchester, Panera— a corporate chain — is part café, part “artisan” bakery, with plush chairs and gourmet grinds. When I arrive, I spot Ayotte in the back, smartly dressed with coffee in hand, milling about, a star among the soccer-mom set that crowds the booths. Ayotte, 42, a former state attorney general, is in the midst of a tight primary campaign. With Sen. Judd Gregg retiring after three...