LITTLETON, N.H. — Former GOP presidential candidate Sen. John McCain (Ariz.) was in his element Saturday — giving hugs, posing for pictures and shaking hands beside an oversized picnic pavilion at the Veterans of Foreign Wars post here in Littleton. He was asking Granite Staters for their votes in the first-in-the-nation primary. But this time, not for himself. “Lindsey Graham, he’s my man!” McCain declared with a chuckle,...