Exhilarating because when Jon stood in front of a town hall, he would ask the people not just for their votes but for their trust. Each time, Mary Kaye says, she'd get a chill.
Every time they'd show up at a New Hampshire grocery store, people would tell Jon he was rational, honest, a common-sense guy, she said, preferring as always to speak more about her husband than herself.
He also represents what she calls a "carved-out hole that has no home," consisting of Republicans, Democrats and independents seeking something more than posturing pols.
"Jon is never going to compromise," Mary Kaye said. "He stayed true to his core principles."
For the duration of the seven-month campaign, the Huntsmans worked "24 hours a day," she said, a pace that took a toll.
"What goes out the door is exercise and a good diet," she said. "I was thrilled to carry a suitcase in the airport, and take the stairs."
Meanwhile, the couple juggled their younger daughters, Gracie and Asha, who usually stayed with other family but joined their parents as often as they could. Mary Kaye said she talked every day with her sons, one at the Naval Academy and the other at an academy prep school.
Turns out, 12-year-old Gracie had a pretty astute understanding of the campaign.
"Jon called her his senior political adviser," Mary Kaye said. "She gave us great, sound advice. After Jon's town halls, she'd say, 'Dad, you forgot to say this, you forgot to ask that.' "
Mary Kaye also became close with Anita Perry; their husbands had known each other well as governors.
"I'd see her at the debates. We were there to comfort one another," she said. "We texted every day."
And they'd talk about the "roller-coaster ride" of campaigning, how one minute you're at the top, the next right down at the bottom.
Last Monday, Jon Huntsman, facing a tough run in South Carolina, dropped out of the race and endorsed his fellow Republican and Mormon, Mitt Romney. There could be more politics in his future.
"I always said, 'He's a rising star, not a shooting star.' It was a slow rise, but substantive," Mary Kaye said. "He's a gentleman, a statesman."
Soon the family will be heading for Coronado, Calif., where they have a condo and where Jon spent much of his youth.
"Jon's got a lot of thinking to do about what he's going to do. There are lots of options," Mary Kaye said.
For her, "Nothing is as therapeutic as walking on the beach. You're drained. You need a few days to get centered again, happy, and then you move forward."
Peg McEntee is a news columnist. Reach her at email@example.com, facebook.com/pegmcentee and Twitter.