The New York Democrat, speaking at the end of an hour-long meeting with undecided voters, spoke with obvious emotion as she explained why she endures the pressures of a campaign that offers her little chance to exercise or eat right.
Clinton, once considered the front-runner, is now trailing Illinois Sen. Barack Obama in New Hampshire polls, and former Sen. John Edwards of North Carolina, who beat Clinton in Iowa, is gaining ground in the latest polls here.
"And some people think elections are a game. They think it's: who's up or who's down. Some of us put ourselves out here and do this against some pretty difficult odds. And we do it -- each one of us -- because we care about our country."
The moment came as a dramatic coda to a campaign in which she has largely offered voters policy prescription. Guarded about her private life, Clinton has been reluctant to give the public a glimpse at her authentic self.
Whether she was exhausted or moved by the question, her answer won praise from the dozen or so voters sitting with her at a table at Café Espresso.
"I loved that," said Elizabeth Holcomb, 36, of Exeter, N.H. "That's a side of Sen. Clinton that people don't see very often. Some of us want that. I think it's lovely. I don't question her passion after today."
The question was posed by Marianne Pernold Young, a 64-year-old freelance photographer who lives in Portsmouth. Young also asked Clinton who does her hair.
Clinton said: "Luckily, on special days I do have help. If you see me every day and look on some of the websites and listen to some of the commentators, they always find me on days I didn't have help."
She described how difficult it is to look her best.
She said, "as difficult as it is to keep up what I try to do on the road -- like occasionally exercise and try to eat right -- it's tough when the easiest food to eat is pizza.
"I just believe so strongly in who we are as a nation, so I'm going to do everything I can to make my case and let voters decide."
Clinton's response came a day before the New Hampshire vote. Since losing the Iowa caucus, she has had little rest. She immediately flew from Des Moines to New Hampshire, arriving before dawn on Friday. She quickly began a full schedule of campaign appearances, where she has been taking questions from voters for sessions lasting up to two hours.
Young said she was moved by Clinton's reaction. She called it her finest moment in the hour-long meeting, and said Clinton needs to show more of that personal side on the campaign trail.
"I loved it! I loved it!" Young said. "I think it was genuine. It wasn't issue-based. It hit a nerve and it was real."
She added that Clinton needs "to show more emotion and [give] shorter answers. Shorter answers. I looked around the room and everyone was playing with their Blackberries.
"I know they say women shouldn't cry and neither should men," she said, "but so what?"
In the past, New Hampshire has not been kind to presidential candidates who show emotion. In 1972, Sen. Edmund Muskie (D-Maine), the establishment candidate, choked with anger and seemed to cry because of some unflattering articles in the local newspaper. Sen. George McGovern of South Dakota finished a surprisingly close second and went on to win the nomination.