Stephanie Hundley is an enthusiastic Bernie Sanders supporter. The 28-year-old from Waterloo is also enthusiastic about the fact that she's not going to vote for Hillary Clinton just because she's a woman.

"I don't think she's the woman to be representative of women," Hundley said. She ticked off a list of Clinton criticisms: the "damn emails," the "flip-flops," her vote to go to war in Iraq. Citing Sanders' record of supporting women's rights, Hundley said his overall views embody hers more than Clinton's do. "It's weird that an old, white guy would represent women better than an actual woman."

Many millennial women, like Hundley, want to deal a repeat upset to Clinton in the Hawkeye State. Eight years ago, Clinton lost the women's vote in Iowa to another candidate promising change in Washington. Entrance polls showed that the only group who favored her were the oldest women — those over 65. A similar pattern could emerge again this year. Iowa women do prefer Clinton, according to the final Des Moines Register poll before the Iowa caucuses, but that support is strongest among women over 45.

The split has exposed a fault line around feminism in America, between women who grew up in an era when they weren't allowed to wear pants to work, for example — and young women who have never known the kind of discrimination and stereotypes their mothers faced.

A recent poll even found that young women supported Sanders in greater numbers than young men. A January online survey of young voters from USA Today and Rock the Vote showed that women under 35 supported Sanders by an almost 20-point margin, compared to men's 4-point margin.

Dueling Identities: 'Young' Vs. 'Woman'

Katherine Hillicker is a freshman at Michigan State who came down to Iowa to canvass for Sanders. She sees near-universal support for Sanders among their peers at Michigan State, and she thinks she knows why.

Young people, she said, "have grown up in this situation where the economy has been crap, and we're going to college, and it's costing a ton of money." She and her friend, fellow Michigan State student Mackenzie Pollick, say they think Sanders appeals more to young people on those economic issues.

As for gender? It was an afterthought for them. "I think you need to care more about the issues than the gender," Hillicker said.

Pollick added, "As much as I'd love a woman to be president, it doesn't affect my views much."

The age gap is stark. A recent Quinnipiac poll found that Sanders bests Clinton among 18- to 44-year-olds, 78 percent to 21 percent. But support for Clinton seems to grow with age: 53 percent of 45- to 64-year-olds chose her, along with 71 percent of people 65 and older.

Both Clinton and Sanders have made a point of appealing to both women, on issues of reproductive rights and equal pay, as well as young voters, on student debt. However, the Sanders campaign's promises of sweeping change seems to have helped him win over Iowa's youngest voters, and he's doing everything he can to capitalize on that popularity.

In addition to hitting young people's economic worries hard in his speeches, the Sanders campaign has also been working to mobilize the youngest Iowa voters on caucus night. In its " Go Home for Bernie" push, the campaign is driving young people away from college towns, like Ames and Iowa City, to their smaller Iowa hometowns, to better spread his support all over the state. That's important in a caucus state that won't report raw vote, but shares of delegates.

'There's Going Go Be A Lot More Elections In Our Lifetime'

Some young voters say it would be nice to have the first female president — but that's about as excited as they get.

"We're still young," said Olivia Vogel, an Iowa State student, "and there's going to be a lot more elections in our lifetime, that right now I wouldn't choose just because she's a woman."

Vogel attended a Clinton rally in Ames on Saturday, but isn't supporting a candidate yet.

"I feel like I grew up in a pretty equitable society where I think men and women are based fairly," said Vogel's friend Julia Zappa, a sophomore at the University of St. Thomas in St. Paul. Though she was at the Clinton event, she said she supports Republican Chris Christie. "I think for a younger generation, we don't need to rush for a woman to become president, because I feel like it'll happen, so I don't want to rush."

The long string of presidential elections ahead of them is full of the possibility — or even the probability, as Zappa sees it — of a female president. That means other issues feel much more pressing right now.

"I don't think voting for a woman is particularly novel for them," said Dianne Bystrom, director of the Carrie Chapman Catt Center for Women and Politics at Iowa State University. "The fact that the nation elected its first African-American candidate in 2008, it's kind of taken the edge out of those narrow parameters of who can be president."

If that's true, the gender card — which Clinton is playing more forcefully this year than in 2008 — may be less effective now for some young voters.

But their minds may change as they age.

"I think younger women will face some discrimination in their lives, but when they're young, they probably haven't," Bystrom said. Older women, meanwhile, "feel that it's about time to have a woman president," she added.

Of course, the reasons anyone supports Clinton (or Sanders) are far more nuanced than voting for a gender. Many women — old or young, supporting Clinton or Sanders — say that gender isn't a factor at all in choosing a candidate.

And some Sanders-supporting women say they considered the draw of caucusing for a woman, but it ultimately couldn't sway them. Likewise, for many Clinton supporters, who are drawn in by her gender, it's simply one of many reasons.

However, it is a reason that amps up their enthusiasm.

"It's about time we caught up with the rest of the civilized world," said Maureen Ekeland of West Des Moines, who attended a Clinton speech in Ames with her daughter and granddaughter. All three are Clinton supporters.

"It's don't think it's the only thing, and it might not be the main thing. But absolutely — it would be an amazing thing," said Jennifer Ruggle of Waukee, Ekeland's daughter.

For Older Women, The Time For A Female President Is Now

At the other end of the spectrum from the college students attending the event, who feel they have a lifetime to put a woman in the White House, there are the women who say time is running out. One Clinton volunteer said those women motivate her.

"There are so many children that need to grow up in a situation where it's normal to have a female president," said Kim Frederick of Houston. Frederick told NPR's Tamara Keith the story of an elderly woman she met at a Clinton rally in 2008, when Frederick was also a volunteer.

"And she said, 'Please, I'm 94 years old,' " Frederick said. "I can't get out there and volunteer. Can you please make this happen? And I promised her I would. And it didn't happen in 2008, and she's probably not around anymore, but there's another 94-year-old woman in a wheelchair that I have to do that for this time. And we're going to make it happen."

Gender Matters In The General

Importantly, it's not that supporting Sanders means rejecting Clinton. Many female Sanders supporters who spoke to NPR said they'd support Clinton as a general-election candidate (and many of her supporters say the same of Sanders).

And general elections make it clear that it doesn't make sense to talk about the "woman voter," as the Atlantic reported in 2012. While it's true that women tended to support Obama in the past two presidential elections, there are factors beyond gender at work here. Single and minority women have tended to support Obama, for example, while white and married women went for Mitt Romney.

Once the Democratic candidate is chosen, that's when the battle for women's votes will get even more important, Bystrom pointed out.

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