DES MOINES — When Tanya Keith and her teenage daughter Aviva Jotzke learned that their favorite Democratic presidential candidate, Sen. Cory Booker of New Jersey, had dropped out of the race a few weeks before the Iowa caucuses, they cried and mourned with fellow supporters.

Then they began to assess their options.

Over the next seven days, they would attend three campaign events for different candidates, have numerous conversations with each other and friends who had committed to other candidates, and endure what seemed a never-ending weighing and reweighing of what issues and leadership traits matter most to them.

“I am not comfortable in the undecided space,” said Keith, 48, who committed to Booker at a Memorial Day picnic in 2019 and was his precinct captain for her neighborhood. “I don’t like to sit and mull and wait.”

Their desire to commit early is rare this caucus season. Iowans always feel a special responsibility in kick-starting primary voting, but that sentiment has been heightened this year by the party’s determination to defeat President Trump, now gestating for more than three years.

Many voters have found themselves paralyzed by indecision as they try to determine not only which candidate they like best but which has the best shot of beating Trump in November.

Polls show an unusually large number of Democrats are uncommitted, and a recent Monmouth University poll of Iowa found 4 in 10 voters said they could change their minds before caucus day.

Their decision-making is complicated by a historically large Democratic field, which has given voters like Keith and Jotzke far more candidates to consider than in a usual year, and the shadow of the 2016 campaign, in which nominee Hillary Clinton lost narrowly in states that typically vote Democratic. Across the state, Iowa Democrats often sound like television pundits as they describe how each candidate might fare on a debate stage with Trump or in balloting in swing states.

Even those who have committed can find themselves thrust back into indecision if their chosen candidate drops out — as Booker did on a recent Monday morning.

Keith loved — and still loves — what she saw as Booker’s kindness and relatability, the way he connected with younger voters, and his call for “baby bonds” that would give every newborn a $1,000 savings account, which she considers “the way to talk about reparations without getting white poor people up in arms.”

She moved to Iowa from New Jersey about 27 years ago, and she and her husband are raising their family in Des Moines’ diverse River Bend neighborhood because “it was important for me to live somewhere where my kids would not assume that white people were just all there was.”

“I just loved how he talked about racial and economic inequality,” she said of Booker. Then she paused and screamed out loud in frustration at his departure.

It took Jotzke, 17, a bit longer to commit to Booker, as she originally signed a caucus card for Pete Buttigieg, the millennial former mayor of South Bend, Ind. She thought that because Buttigieg is gay he would bring a different perspective to the race and have empathy for marginalized communities.

“He didn’t apply it, at least in my opinion, to racial justice and to standing up for trans people and all the marginalized people,” said Jotzke, a junior in high school who will turn 18 about three weeks before Election Day, meaning she is allowed to caucus for the first time in February. “He just didn’t apply it well.”

“And that was sad,” her mom said.

“Yeah,” she said. “It was sad.”

Jotzke switched to Booker late last year, after she talked to the candidate — and he followed up with her. Of everyone in the field, she concluded, Booker was the most empathetic and understanding.

When he dropped out, they didn’t have a second choice and weren’t sure they wanted to commit to anyone else. How could they suddenly support a candidate they had been arguing against as they tried to build support for Booker?

“It’s hard because it’s a mourning of what could have been,” Jotzke said. “I don’t know if there’s anyone as good as him. I don’t want to pick any of the others. I want to pick him.”

Keith was angry that Booker left the race when so many Iowans were still undecided — and that he had been pushed off the debate stage by rules set by the national party. She was invited to attend a house party featuring billionaire Tom Steyer and decided to attend so that she could “scream at him” about “what money has done to this race.” Jotzke had no interest and stayed home to do homework.

When Keith arrived at the party, she saw the beloved former principal of her children’s school and realized she couldn’t make a scene. She was impressed by Steyer’s passion for protecting the environment and his answers on combating racial inequality. She ended up hugging him and posing for a photo. But he did not win her over.

The mother and daughter kept at it. They’ve been campaigning together for years — as a toddler before the 2004 caucuses, Jotzke would go “banging on doors” with her mother for the eventual Iowa winner, John F. Kerry — and they didn’t want to sit out this year’s voting.

They quickly cut their list to the two women in the race: Sens. Elizabeth Warren of Massachusetts and Amy Klobuchar of Minnesota. Jotzke added one more to her list: Andrew Yang, the tech entrepreneur whose ideas she liked, although she worried about his lack of political experience.

“I try to envision the debate stage in the general election, and I think about watching some septuagenarian white man yelling at another septuagenarian white man,” Keith said. “And it just feels wrong to me. And I feel like we need to talk about what’s happening in this country on a level that old white men don’t get. And I think that women, especially moms, understand on a base level what is happening in this country.”

Although both often hear the argument that former vice president Joe Biden has the best shot at beating Trump, they just don’t think that’s true.

“He just keeps sounding like your grandpa that isn’t like overtly racist but still says things that are NOOOOT comfortable with where we are in 2020,” said Keith, who works in historical preservation and, on the side, has written two books about soccer. “Like, I don’t think that he’s a bad person.”

“You still love him,” Jotzke continued. “You still want him in the family.”

“And then Bernie,” her mother said, continuing down the list of septuagenarians. “Why did he not drop out after that heart attack? . . . He’s the only candidate that would be past his expected life expectancy on Election Day. That’s disturbing, you guys, it’s really disturbing.”

On policy, the two know that the candidates have been sorted, often against their will, into two major buckets: the left wing and the centrists, the dreamers and the pragmatics. But when they looked at the field, they saw candidates with positions that seemed similar and uniformly more liberal than those of Clinton just a few years ago.

Four days after Booker dropped out, Jotzke got a call from a Buttigieg supporter. It was not the first entreaty. A few days before, a Sanders supporter had knocked on their door, and their phones had been filling with calls and messages.

Jotzke explained that she wouldn’t caucus for Buttigieg because he hadn’t, in her view, advocated enough for marginalized communities. She found herself making the case for Klobuchar, noting the senator has passed a lot of bipartisan legislation and has won in rural Minnesota counties that Trump won in 2016.

She got off the phone and heard her mother on the phone with a Warren supporter calling from Massachusetts, who had nearly convinced Keith to caucus for the senator.

“Did you just commit to caucusing for Warren?” Jotzke asked. “That’s not okay because I’m leaning towards Klobuchar.”

The two agreed to not make up their minds until they had seen both candidates in person. They mostly agreed on the pros and cons of each: They loved that Warren has such a massive organizing operation in their state and elsewhere. They really liked that Klobuchar is from the Midwest and younger. They liked that Warren has been a leader on liberal issues, but they worried about her promise to provide free college for all, which Klobuchar has said could lead to the working class paying the tuition bills of the rich. They suspected that Klobuchar would be more likely than Warren to make Booker her running mate, but there was no way to know for sure.

There’s one other thing that worried them about supporting Warren: Bernie bros, the avid Sanders supporters who engaged in angry battles with opponents in 2016.

“We both worked on Hillary Clinton’s campaign, and we saw what the toxicity between Bernie bros and Hillary people became, and we’re both real slow to want to engage with that,” Keith said. “His supporters — not him — his supporters are so rabidly tearing into Warren supporters that it’s just a real turnoff.”

Five days after Booker dropped out, the two attended a Planned Parenthood event for Warren in a Des Moines home, and Keith asked the senator about the private 2018 dinner with Sanders during which Warren says Sanders raised doubts that a woman could defeat Trump. (Sanders has denied her account.)

“I believe you 100 percent,” Keith said. “Because I looked at you and I looked at him and I’m like, ‘He did that.’ I know that Bernie Sanders said those things to you. . . . I know what men say to us in rooms and then what they say to us in person to gaslight us.”

Keith said she had “a little PTSD from the Clinton campaign” and asked Warren to share her plans “for shutting that down when you’re the nominee.”

Warren said she and Sanders are longtime friends who “fight for the same issues.”

“What I truly believe is,” Warren said, “we’re going to have to pull together.”

The event deepened Keith’s tilt toward Warren and left Jotzke suddenly conflicted. The next night, they attended a Klobuchar rally in the Des Moines suburbs. Before it was over, they had swapped positions.

Keith found Klobuchar a “very relatable” fellow Midwestern mom who was “tough as nails” and told jokes that made her burst out laughing. She liked that Klobuchar sent her daughter to a public school where a majority of students qualify for free or reduced lunches — just like the schools where she sends her children. She loved that the senator closed with a riff on Martin Luther King Jr. and the need for racial justice and fairness.

“I’m talking myself into Amy,” she told Jotzke.

At the same time, Jotzke was struck by the lack of enthusiasm at the Klobuchar event and worried that the senator didn’t have the personality to energize a crowd or propel people to vote. She also found Klobuchar to be a less polished speaker, saying “um” at least six times in one minute.

“We’ll talk in the car,” Jotzke told her mother.

On the drive home, the two went back-and-forth on the strengths of the two women and the visions for the country they both championed. That night, they were amused to see that the New York Times editorial board had landed at the same place, endorsing Warren and Klobuchar. Together, they watched videos from the board’s interviews.

Warren seemed to have more gravitas, while also being funny and intelligent. While Klobuchar might better connect in intimate settings and small towns, Warren appeared more comfortable in front of massive crowds and on debate stages, they both felt. Plus, both candidates would soon be trapped in the impeachment trial in Washington, putting more responsibility on their Iowa organizers — an area where both felt Warren is stronger.

“Well, that settles it,” Jotzke said, “I’m for Warren.”

Her mother agreed and the next afternoon — as Yang prepared to visit their neighborhood and as Sanders held a rally less than three miles away — the two traveled to Warren’s headquarters to sign yet another commit-to-caucus card. It had been exactly one week since Booker left the race.

The next day, they planted a light-green Warren campaign sign in their snow-covered front yard. They left the Booker sign right where it was.

Amy B Wang contributed to this report.