Senator John McCain’s first town hall in May 1999 was awful. Thirteen people milled around at a nearly empty American Legion Hall in Manchester, and only nine of them were still deciding whom to vote for in the first-in-the-nation primary.

But the Arizona Republican, facing a goliath named George W. Bush with the entire Republican establishment behind him, stuck with it. He took questions in church basements, diners and community centers until the assembled voters ran out of questions to ask. He talked to reporters on his Straight Talk Express bus and made no secret of reaching out to independents.

In February 2000, Mr. McCain shocked the Texas governor with a convincing New Hampshire victory, 49 percent to 30 percent.

Accessibility, honesty, vulnerability and a near-constant presence — Nikki Haley did none of that in New Hampshire against her own goliath, Donald J. Trump, a far different candidate from Mr. Bush but one who also has the aura of inevitability. On Tuesday, she lost New Hampshire’s first-in-the-nation primary.

Maybe it didn’t have to happen that way.

“Seven, 10, 14 days ago, I thought she could have won,” Mike Dennehy, Mr. McCain’s New Hampshire campaign manager and the architect of his improbable victory. “I really did.”