Emily Roskey, 28, in costume as Rosie the Riveter, posed for a photo at a Planned Parenthood event where volunteers worked phone banks. (Star Tribune/The Minnesota Star Tribune)

They are the wild card of the 2018 election: young people jolted by Donald Trump's presidency who are protesting, organizing and registering to vote in record numbers.

Their collective clout could be decisive Tuesday, but will they really show up to vote? History suggests that it would be unwise to bet on it.

Voters who are 18 to 29 typically rack up the lowest participation percentages of any age group. In the 2014 midterm election, about a fifth of people in that age group voted nationally. The number was only slightly higher in Minnesota.

That might be about to change. A new study by the Harvard Kennedy School's Institute for Politics found that 40 percent of young Americans definitely plan to vote.

"I felt like I was morally obligated," said Abby Trevor, 24, an editorial assistant from Bloomington. The 2016 election, she said, made her decide it was time to play a part.

"If it's in our power to turn things around we really have to do that," Trevor said.

Among Democrats ages 18 to 29, 54 percent were sure they'd cast ballots, according to the Harvard study. That's still not great: Gallup found that 82 percent of voters older than 65 were certain to vote.

As of Thursday, 65,447 Minnesotans younger than 30 were newly registered to vote in this election, according to the Minnesota secretary of state. More than 22,000 were 18.

Zach Lindner, 19, a University of Minnesota sophomore from Deerfield, Ill., voted last Monday. Dismay about gun violence got him involved.

"This is our America that we're trying to fix," Lindner said. "I believe in the power of young people."

If Harvard's turnout projections pan out, Democratic candidates are likely to benefit. The Harvard study found that Trump's approval rating among voters under 30 was just 26 percent.

A Star Tribune/MPR News Minnesota Poll conducted Oct. 15-17 tracked voters in the 18-34 range, finding that they favor Democrats over Republicans in the contests for governor, U.S. Senate and state attorney general. By wider margins than all other age categories, they disliked Trump's immigration and trade policies and the U.S. Supreme Court nomination of Brett Kavanaugh.

The Trump presidency is stoking a surge in activism among voters under 30 on campuses across Minnesota and at organizations such as Planned Parenthood.

Donations for advocacy work have doubled and there's been a 190 percent increase in volunteers for its political arm since the 2016 election, said Tim Stanley, executive director of Planned Parenthood's Action Fund. Voters who don't always turn out — youth, people of color and women — "are exactly the people we specialize in," he said.

Republicans are also competing for young voters. Turning Point USA, which organizes young conservatives, has five chapters in Minnesota. The state's 17 College Republicans chapters are working in every congressional district, said Kathryn Hinderaker, the state chairperson and a St. Olaf College senior.

"There's just been a ton of enthusiasm" this year, she said.

The biggest infusion of cash has come from billionaire Democratic activist Tom Steyer's NextGen America. It spent more than $30 million to register young people in 11 states. Minnesota is not among them, but Iowa and Wisconsin are.

The University of Minnesota has a chapter of Swing Left, a national group dedicated to electing Democrats in up-for-grabs U.S. House races. Its members, including Lindner, spent last Sunday making calls for Dan Feehan, the Democratic candidate in Southern Minnesota's First Congressional District.

Izzie Osorio, 18, a freshman from Sioux Falls, S.D., was among them. Trump's policies, she said, are the reason she has decided to become an immigration lawyer. Her parents are citizens but were once in the U.S. without documentation.

She would be active in politics even if she didn't feel threatened by Trump's views. "Even if it's not affecting me, it's affecting the people around me," Osorio said.

"This election means a lot to me," said Neha Upadhyaya, 22, another Swing Left member and a finance major from Medina. "I'm really scared of what happens if people don't show up to vote."

But some of her own friends don't know how to get an absentee ballot or where to vote. "There are so many excuses. I had a friend who told me she didn't vote because she doesn't want to go into the jury pool," Upadhyaya said.

Savannah LaDuke stopped to chat the other day at Rosedale Center. She's 21, lives in St. Paul and studies public health and wellness at the University of Minnesota. She's busy at school and pays little attention to politics and elections.

"I don't feel connected to it, really, and I'm kind of confused," she said. Antagonistic campaign ads annoy and perplex her. "The commercials are like, 'he did this' and 'she did that,' " she said. LaDuke isn't registered to vote and thought it was too late to do so. (It's not — Minnesota has same-day voter registration.)

Kayla Wallace, 18, also talked politics at the mall. "I just have really never been interested," she said. One reason is that she's open-minded, she said: "When someone says their opinion and someone else says a different opinion, I always can see both ways."

Wallace, who lives in Stillwater and plans to study medical coding online, said that her family has never been active in politics, either. "I just feel like whatever happens, happens."

Planned Parenthood volunteers, including Trevor, aren't leaving anything to chance. Almost 30 people worked the phones last Tuesday night.

Emily Roskey, 28, an outdoor educator from Framingham, Mass., likes working with people who care about issues that matter to her.

Volunteering also eases her guilt over 2016. "If everybody had done a little bit more or if we had worked together," voters divided between Hillary Clinton and Sen. Bernie Sanders might have united to beat Trump, she said.

"I've never felt the urgency like I do right now," said Jayne Discenza, 27, a University of Minnesota grad student from St. Paul who studies public policy. Progress can be slow, but it's real, she said. "Sometimes you change a single mind, and that's worth it to me."