PORTSMOUTH, N.H. — If Hillary Rodham Clinton isn’t crying now, maybe she should be.
At Cafe Espresso, the diner here where Mrs. Clinton’s teary-eyed response to a voter’s question in 2008 helped propel her to a comeback win in the state’s primary the next day, voters are longing for another glimpse of the passion or emotional investment that she showed back then.
“When President Obama ran, there was such passion in his speeches. I don’t get that passion from Hillary,” said former state Rep. Lynn Joslyn, who was at the cafe Tuesday for breakfast with her husband, Jack.
Mrs. Joslyn, who eagerly volunteered on Mr. Obama’s 2008 campaign in New Hampshire, said that she is a “fence-sitter” this time around, unsure whether to pull the lever for Mrs. Clinton or Sen. Bernard Sanders in the state’s first-in-the-nation primary.
“What I read about Bernie Sanders — I haven’t actually heard him, but my friends that have were touched by the passion. He speaks to the middle class. He understands what our problems are. He knows where we are at,” she said. “With Hillary, I just feel a remoteness to people like me.”
Her discomfort with Mrs. Clinton, who remains the front-runner for the Democratic presidential nomination, was shared by several customers at Cafe Espresso and reflect a growing problem for Mrs. Clinton with voters who don’t think she is authentic.
The patrons complained that the former first lady, senator and secretary of state was overly scripted, methodically following a political playbook and not running on heartfelt ideals.
That authenticity gap has emerged as a major challenge for Mrs. Clinton in the Granite State, where voters want a personal connection with presidential candidates. It also threatens to become her Achilles’ heel in a general election race.
“Throw the playbook away. Be a Hillary Clinton that’s a professional woman, a mother, a grandmother — someone who has been in a grocery store lately, someone who would actually have to go into a hospital and wait in line to get in the ER, someone that would have to tangle with the TSA at the airport, someone who knows what it’s like to go into the store and buy a Hallmark card, for heaven’s sake,” said Mrs. Joslyn.
Mrs. Clinton has attempted to humanize her campaign. On the campaign’s first road trip to Iowa, Mrs. Clinton made an unannounced stop at a Chipotle and was unnoticed by other customers when she purchased a burrito bowl at the counter.
On the stump, she often talks about being a new grandmother and how it has made her more determined than ever to leave the country in better shape for future generations.
Still, several Democratic voters at the cafe said that Mrs. Clinton’s inability to relate to everyday people — the same people Mrs. Clinton has said she wants to champion — is a bigger problem than the email scandal dogging her campaign.
Mrs. Joslyn said she was friends with Marianne Pernold Young, who asked the question in 2008 that brought tears to Mrs. Clinton’s eyes, an episode credited with delivering her a New Hampshire victory after an embarrassing third-place finish in the Iowa caucuses.
Mrs. Clinton was at the cafe the day before the primary election in Jan. 2008 to meet with undecided voters, when Ms. Pernold Young asked how she manages to get up every morning to face a grueling political campaign.
“It’s not easy. And I couldn’t do if I just didn’t, you know, passionately believe it was the right thing to do,” said Mrs. Clinton.
“This is very personal for me. It’s not just political. It’s not just public. I see what’s happening. And we have to reverse it,” she said, choking up. “Some people think elections are a game, and they think it’s like who’s up or who’s down. It’s about our country. It’s about our kids, [our] futures. And it’s really about all of us together.”
Nearly eight years later, Charlie McDermott, a retired businessman having breakfast in one of the cafe’s booths, said that Mrs. Clinton will have to do more than shed a few tears to convince voters she is for real.
“I think people are hungry for a politician who isn’t so heavily involved in the system,” he said.
Mr. McDermott said that the country faces enormous challenges, and Americans want a leader who they believe in. He said Mrs. Clinton needed to be more like her husband, former President Bill Clinton.
“She has a harder time warming up, where he can smile and do things and naturally people gravitated to him. I think she has a hard time doing things like that,” he said. “It’s just the personality. Some people are charismatic. Some people aren’t. You don’t know why.”
“We need a shining light. It would be nice if Clinton was that,” he said.
Mr. McDermott said that Mr. Sanders reminded him of former President Harry S. Truman, a Democrat known for straight talk.
“One thing you’ve got to like about Bernie Sanders is he kind of reminds you of Truman, in a far-fetched way, maybe. But you kind of believe that if he says he’s going to do this, he’s going to do that,” said Mr. McDermott.
Mr. Sanders, the Vermont independent and die-hard socialist who has emerged as Mrs. Clinton’s chief rival, has been drawing the largest crowds of any presidential candidate this year and has steadily gained on Mrs. Clinton in the polls.
He surged past Mrs. Clinton, beating her 44 percent to 37 percent, in a Boston Herald/Franklin Pierce University poll last week.
The survey showed that Mrs. Clinton’s favorability rating remained high, about 80 percent, among the state’s likely Democratic primary voters. But 51 percent said they were not enthusiastic about her candidacy, though they could vote for her. Just 35 percent said they were excited about her as a candidate.
For Mr. Sanders, 44 percent said they were excited about his candidacy. About 36 percent support some of his ideas but don’t think he could win a general election against the Republican nominee, according to the survey.
Mr. Sanders also is gaining on Mrs. Clinton in national polls. He trailed Mrs. Clinton by 19 points, 49 percent to 30 percent, among Democratic primary voters in a Fox News poll this week. Mrs. Clinton enjoyed a 29-point lead in late July/early August and a 46-point lead in June.
David Hadwen, owner of Cafe Espresso, said he had invited Mrs. Clinton to return to the restaurant but hadn’t heard back from the Clinton campaign.
Mr. Hadwen said he didn’t know if he would vote in the Democratic primary or who he would vote for if he did. But he said a return visit by Mrs. Clinton might help her campaign.
“She’s slipping,” he said.