Less than a week after a gunman killed 17 people at Marjory Stoneman Douglas High School, shooting survivor and high school junior Jaclyn Corin was at the Florida state Capitol.

In Tallahassee, she led a group of more than 100 students to attend more than 70 meetings with state legislators, urging them to pass measures that might prevent mass shootings like the one that had just ravaged their school.

Corin, 18, called the trip "eye-opening." She said she met several legislators who weren't receptive to what she had to say. That convinced Corin and other Parkland shooting survivors – many of whom were not 18 – that there was only one thing they could do to ensure their demands would be met.

“You can always lobby, and you can always protest," Corin said. “But the only direct way to actually get involved is to vote.”

Eight months later, voters of Corin's generation are a highly watched cohort for the midterm elections. Voters ages 18 to 29, whose turnout has historically been low in midterm elections, could help decide close races across the country.

Matt Deitsch, a 2016 graduate of Marjory Stoneman Douglas, had two younger siblings who survived the shooting. Deitsch lobbied in Washington, where he met with "some people who were incredibly divisive and ignorant and rude."

"We realized really quickly that we can’t solve this problem when we have those types of people in office," said Deitsch, 21.

Young people aren't typically a reliable voting bloc. They're transient, frequently changing addresses. They're busy with college and work. Often they're apathetic about politics, or they worry their votes won't matter.

In the 2014 midterms, Generation Xers and millennials accounted for 53 percent of eligible voters but cast 36 million votes – 21 million fewer than the boomer, silent and greatest generations.

“It’s not about who are you going to vote for in November, it’s about whether or not you’re going to vote," said Olivia Bercow, a spokeswoman for NextGenAmerica, a liberal group focused on turning out young voters.

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Could this year be different?

The 2018 midterms are happening against a backdrop of political and cultural divides. Activism on the left has surged nearly nonstop since President Donald Trump took office.

The day after Trump's inauguration, more than 3 million protesters convened in Washington and cities across the country for the Women's March, probably the largest single day of protest in U.S. history.

Subsequent protests and marches surrounding immigration, climate change and gun violence also drew large crowds.

It's all a recipe, some experts said, for youth turnout to finally make a difference.

John Della Volpe, director of polling at the Harvard Kennedy School Institute of Politics, has studied the youth vote since 2000. He compared today's environment with the political sentiment that followed 9/11: high emotions and a desire for action.

“I think now we have a moment that reminds me, from this perspective, of the post-9/11 moment, where politics matters to a new generation of young Americans who are considering voting for the first time," he said.

Today's young liberals want their politicians to address deep, structural inequalities, Della Volpe said. In general, they're more concerned about the health of American democracy and American capitalism than their parents are. They care about race, access to education, health care and climate change.

"The issues that Bernie Sanders put on the table back in 2016 are very much the issues that are driving the enthusiasm in 2018," Della Volpe said.

Experts said enthusiasm is higher among young Democrats than young Republicans this cycle. A poll in October by the Institute of Politics found that 54 percent of 18- to 29-year-old Democrats planned to "definitely vote," compared with 43 percent of Republicans and 24 percent of independents.

Young voters entering the workforce in a strong job market will be motivated to vote Republican, said Charlie Kirk, founder of Turning Point USA, a conservative organization aimed at energizing college students.

"It's a tough economy to argue against," he said.

More divisive issues are at play, too. Kirk highlighted the confirmation hearings for Supreme Court Justice Brett Kavanaugh, who testified about sexual assault allegations made against him by professor Christine Blasey Ford, as a motivating force this election cycle for young Republicans, many of whom view political correctness on their campuses with distaste.

“A lot of our young conservatives are energized by how disgusted they are with what they see on the left," Kirk said.

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The Parkland effect

A significant part of surging enthusiasm among young people, mainly on the Democratic side, can be traced back to Corin, Deitsch and other students and graduates of Marjory Stoneman Douglas High, who have turned anti-gun violence sentiment into a serious political force.

“We realized very early on that the only way we can create substantial change is to vote morally just leaders into office,” said Deitsch, chief strategist at March For Our Lives. “Until we actually vote out these politicians that pick money and power over human life, then we’re not going to get anywhere."

March For Our Lives, the organization that sprung from the Parkland students' early activism and is still run by the students themselves, is nonpartisan and doesn't endorse specific candidates. But it has worked feverishly to turn out young voters.

“With young people it’s about making them realize what’s actually on the ballot,” he said. “Guns are on every ballot."

Since February, March For Our Lives leaders have organized a day of nationwide marches, targeted young voters around the country via two 60-day bus tours and involved celebrities – Deitsch said the organization's website briefly crashed when Ariana Grande shared a link to it.

Experts say those kind of tactics are working.

“Young people are often turned off by the gamesmanship of politicians, and the Parkland students and their friends never were that," said Kei Kawashima-Ginsberg, who directs the Center for Information & Research on Civil Learning and Engagement (CIRCLE) at Tufts University. "They were clearly about movement, and maintained positive attitude about participating.”

In Florida – whose gubernatorial race between Democrat Andrew Gillum and Republican Ron DeSantis involves two relatively young candidates on opposite sides of the ideological spectrum – the youth vote could be especially significant.

According to a TargetSmart analysis, the share of registered Florida voters ages 18-29 increased by 8 percentage points in the months after the Parkland shooting. Other key battleground states, including Arizona, Indiana, Pennsylvania, Nevada and Virginia, also saw sizable rises in youth registration.

That group may have been decisive in the Democratic gubernatorial primary, which saw Sanders-backed liberal Gillum edge out Gwen Graham, the establishment choice.

“He was a candidate that’s really excited for young voters but wasn’t really getting the attention he deserved," Bercow said.

NextGenAmerica, which is backed by liberal billionaire Tom Steyer, poured significant resources into the Florida Democratic primary, and according to their data, turnout in youth-heavy precincts in Tallahassee – where Gillum is mayor – was five times higher this year than in the 2014 primary, with 75 percent of the vote going to Gillum.

Other primary contests suggest that youth turnout could be higher than average this year.

In Massachusetts, Kawashima-Ginsberg said, polling didn't necessarily predict the victory of liberal Ayanna Pressley over longtime incumbent Mike Capuano for a House seat representing part of Boston. Young voters – particularly college students in Boston – may have played a key role in that race.

“There seems to be an underestimation of young people’s impact compared to what’s happening," she said.

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