DUBUQUE, Iowa — Molly Smith spent dozens of hours this fall making calls for the presidential campaign of Sen. Elizabeth Warren (D-Mass.). She went to see Warren in person; she had the senator’s liberty-green posters up in her dorm. A sophomore at the University of Dubuque, Smith was eventually hired by the campaign as an intern, becoming an official Warren representative on campus.

But then, she started having doubts.

When voters at the other end of the phone line asked her to explain why she was choosing to support Warren, she says, she realized she didn’t know quite what to say.

“I would just kind of gave them the same spiel everyone else was giving: that she’s here to fight corruption, she wants systemic change, whatever … we’ve all heard it.” As she was phone banking, Smith says, she realized, “I don’t fit in here.”

Smith quit her internship a few weeks later. At Monday night’s Iowa caucuses, the first voting event of the 2020 presidential elections, she’ll be caucusing for Sen. Bernie Sanders (I-Vt.).

Since Warren’s support peaked in the fall, polls have shown her steadily losing ground in Iowa. Her support among the youngest voters, 18- to 29-year-olds, in particular, has plummeted. In October, 38 percent of this age group in the state supported Warren, according to polls. Now, just 16 percent say they plan to caucus for her. It’s not hard to figure out where the 20-somethings are going. Sanders, now surging in the polls overall, has made especially large gains with young people. Forty percent of Iowa voters in this age group — and 53 percent nationally — now say they now plan to support Sanders.

Sanders is known for his die-hard base of millennial supporters, many of whom have stayed by his side since he ran for the Democratic nomination in 2016. But in interviews with over a dozen Iowa voters in the youngest voting bracket, the senator’s message seemed to be reaching young people far beyond this core base, some who didn’t know much about the election, or had been planning to support a different candidate earlier in the race. A few said they’d recently made the switch from Warren to Sanders.

At the University of Iowa (UI) in Iowa City, the Sanders campaign is everywhere. Every day, the Sanders student group stakes out a different room in the student union building to use as their “headquarters,” dispatching canvassers and organizing texting campaigns to reach as many students as possible. Every student interviewed said they see far more signs and supporters for Sanders than any other candidate. Last week UI’s student newspaper, the Daily Iowan, endorsed him.

“Usually you see them outside on the walkways,” says Sarah Smith, a UI freshman. “But the other day my friend and I were studying, and one of them came up to us. I was like, ‘Really? You’re inside the building now?’” Earlier in the year, Smith would sometimes pass a few people canvassing for the Warren campaign, she says, but she hasn’t seen them in a while.

Sanders is generally considered the “cool” candidate” in Iowa City, says Esme Bengston, 24, who works at a bar downtown.

“People will be like, ‘I know you’re caucusing for Bernie, I know you are,’” she says. “It’s just assumed.” Personally, Bengston doesn’t understand the appeal. She is planning to caucus for Warren.

But even Warren supporters are skeptical about their candidate’s ability to win here, in a city overrun by students. Lately, Warren hasn’t had much of a presence on campus, says freshman Erin Kresse, who is deciding between Warren and former South Bend, Ind., Mayor Pete Buttigieg.

“I don’t know if it’s that her campaign hasn’t been focusing on young people, but I haven’t been hearing much about her,” says Kresse.

Other students said they’ve been seeing more negative coverage of Warren, especially after the dispute between Warren and Sanders leading up to and at the January Democratic debate, when Warren claimed Sanders said he didn’t think a woman could be president, and Sanders denied the conversation ever happened. After that, Sanders supporters at UI took to Twitter, says sophomore Maddy Ackerburg.

“Twitter that night was just crazy,” says Ackerburg. “All these people were coming for [Warren].”

Up until recently, Ackerburg had been planning to caucus for Warren. When the senator came to campus in the fall, Ackerburg went to see her. She loved everything about Warren’s message, especially her commitment to always have a plan. She brought a poster home from the rally and hung it up in her dorm. But the exchange between Sanders and Warren at the last debate “kind of freaked me out,” Ackerburg says.

“It all seemed a little sketchy to me. I mean, I follow Sanders. It seems like he’s always supported women.”

After the debate, she stayed up late, watching old videos of Sanders in her sorority house. She found one from 1988: In it, Sanders says he believes a woman could be President.

“I kind of had PTSD flashbacks to Hillary and Trump in 2016,” Ackerburg says. “It’s like, who can I trust? What candidate can I fully support?”

Multiple people said they’d moved away from Warren because they’re worried they can’t trust her. Especially after the latest dispute between Warren and Sanders, Smith says, people online have been pointing out Warren’s past inconsistencies: how she claimed to be Native American, how she used to be a registered Republican.

“I’m now seeing all this coverage saying, ‘She’s been lying about this,’ ‘She’s been lying about that.’ That’s really thrown me off,” Smith says. “I want to make my decision based on, who do I really trust?”

She appreciates that he’s been saying the same kind of things since he started his political career in the 1980s.

“But I feel like Warren just popped up out of nowhere,” she says.

She’ll take the candidate with the track record, she says, over the one with the plan.

Caucusing in Iowa can take hours. What are you supposed to do with your kids?

It’s not as simple as hiring a babysitter