And it's not just young women. At rallies across New Hampshire, women from every generation have flocked to Bernie Sanders' events.
They sport "Grandmas for Bernie" buttons, laud him for his vision, and seem content to pass up the opportunity to put Clinton on a historic path to the White House, betting that there will be another chance down the line.
"That ceiling will be shattered at some time and I just think it takes the right person to do that and right now she is not the right person for me," said Ann Kaiser, a gray-haired grandmother from Hampton, New Hampshire, who is supporting Sanders. "I think she would be very vulnerable. She would be hit so hard, in so many sectors that I think it would be tough for her to win."
Kaiser, who said she voted for Clinton in the 2008 primary, attended a Sanders rally in Portsmouth with her granddaughter, who echoed her sentiments.
"I did start out this election supporting Hillary because I thought it's time to have a woman president -- we just took a huge leap and bound, electing someone who is an African-American, why can't we have a woman?" said Emily Smith, 19, also of Hampton.
"But then Bernie ran for president and I loved his ideas. It's outrageous that I'm going to be $80,000 in debt" after college, she said. "It's time for a political revolution and it's time to pay attention to the middle class because we're diminishing."
The former secretary of state lags behind Sanders by 11 percentage points among women, 53% to 42%, according to the latest CNN/WMUR poll. Her struggle to attract women voters in the Granite State reflects Sanders' overall strength in the state that borders his Vermont home base; he leads her 61% to 35% in the poll conducted February 4-February 8.
Still, Sanders' ability to win over women voters -- long considered Clinton's strongest base -- suggests that she could struggle to piece together a reliable coalition in upcoming states as well.
For Clinton, it's a reversal from 2008, when in a mutli-candidate contest, she earned 46% of the women's vote in New Hampshire and won the contest by 2 percentage points. Women will likely make up the majority of Democratic primary voters in most states as they did in 2008, and winning those voters will drive overall success.
In 2008, Clinton largely carried the women's vote in states she won and lost the women's vote in states she didn't. When she ended her campaign in June of that year, she told supporters: "Although we weren't able to shatter that highest, hardest glass ceiling this time, thanks to you, it's got about 18 million cracks in it, and the light is shining through like never before, filling us all with the hope and the sure knowledge that the path will be a little easier next time."
Now, if she is to close the massive gap between herself and Sanders, Clinton will have to again solidify her support among women, starting with New Hampshire on Tuesday. As the campaign moves on to other states, she will particularly need to sharpen her appeal among younger women, who are more likely to back her than their male counterparts but, much like them, have broken for Sanders overall.
To that end, the Clinton campaign has flooded New Hampshire with women surrogates hoping to wrap her race in the larger struggle for women's equality.
Sen. Debbie Stabenow of Michigan told a group of Clinton volunteers that the "real revolution" is electing the first woman president.
Sen. Amy Klobuchar of Minnesota reminded that same group of "how important this historical moment is for us."
And in the last Democratic debate, Clinton framed her gender as an anti-establishment credential.
But other attempts to court young women voters have not gone so well.
Famed feminist and Clinton supporter Gloria Steinem had to backpedal this weekend after she suggested that young women voters flocked to Sanders to attract boys.
Former Secretary of State Madeleine Albright, repeating one of her most famous quotes, told young women that they should support Clinton and that "there's a special place in hell for women who don't help each other."
And Bill Clinton chastised the band of online Sanders' supporters known as the "Bernie Bros," who have trolled Clinton supporters online. In one instance, the former president said, a progressive blogger who wrote a favorable column about Hillary Clinton was compelled to post it under a pseudonym out of fear of blowback from Sanders proponents.
"She and other people who have gone online to defend Hillary and explain -- just explain -- why they supported her have been subject to vicious trolling and attacks that are literally too profane often, not to mention sexist, to repeat," Clinton said.
Aiming to tamp down some of the online trolling, which has been chronicled by prominent women progressives like Joan Walsh, Mike Casca, Sanders' director of rapid response, tweeted last month: "If you support @berniesanders please follow the senator's lead and be respectful when people disagree with you."
In a CNN interview with Jake Tapper, Sanders put it more bluntly.
"It's disgusting; we don't want that crap," he said.
While Sanders has outpaced Clinton among white women here, he has yet to show any strength among a more diverse pool of women. Although there is little reliable polling of black and Latino women, two groups that will help decide the next contests in South Carolina and Nevada, Clinton is dominant among both men and women in those voting blocs. For instance, the latest NBC News/Wall Street Journal/Marist poll in South Carolina shows Clinton leading Sanders among African Americans by 57 percentage points and, as in other demographic groups, women traditionally have higher turnout rates.
"She hasn't had an opportunity to see how she is doing with women of color, so women of color's voices have been left out so far," said Kelly Dittmar, a political science scholar at the Center for American Women and Politics at Rutgers University in New Jersey.
Clinton has spoken out on women's issues for decades and most famously declared at a 1995 World Conference in Beijing that "human rights are women's rights and women's rights are human rights." Because of her longtime support of feminist causes, she has been embraced by organizations like Emily's List and Planned Parenthood and supported by many historic leaders of the women's movement.
Sanders has touted his "100% Planned Parenthood voting record," and likened his grassroots campaign to the struggle for women's rights.
Dittmar said Clinton has been better than her surrogates in trying to appeal to young women. She tells them she will support them even if they don't support her.
"She does need to be careful about her surrogates and the people who are talking for her. We don't want it to be [that] young women don't know what they are talking about; that's not fair," Dittmar said. "But that's the generational divide and it's led to creating a narrative about who is more feminist, Bernie Sanders or Hillary Clinton. Well that all depends on how you define feminism."
At Sanders' final rally of the New Hampshire race, supermodel and actress Emily Ratajkowski defended young women and feminists who support the Vermont senator over Clinton.
"I'm here because I support Bernie Sanders; I'm not here for the boys," she said, alluding to Steinem's remarks. "But yeah, I want a female president so that I can say to my daughter one day, 'You, too, can become president of the United States.' I believe in that symbolic importance.
"But I have seen symbolism in election, symbolism that fails the people that so desperately need the action to make change," Ratajkowski added. "I want my first female president to be more than a symbol, I want her to have politics that can revolutionize."