Many Democrats say the most important quality they look for in a 2020 candidate is that the person can beat President Trump. But this might not be true of younger Democrats, many of whom are saying that they care more about a presidential candidate’s policies — and less about their chances of beating Trump.

Recent polls from YouGov/HuffPost and Gallup show an age split on whether voters prioritize policy or electability. Both polls found that younger Democrats tended to prioritize nominating a candidate whose positions on issues were closest to their own over a candidate who they believed had the best chance of defeating Trump. Conversely, older Democrats were more likely to want an electable candidate even if they disagreed on the issues.

And this generational divide may be reflected in the patterns of support for former Vice President Joe Biden. Voters of all ages often name Biden as the candidate with the best chance of beating Trump. But a Quinnipiac University poll from early July found that while 28 percent of Democrats over 50 rate Biden as their first choice, just 17 percent of Democrats between 18 and 49 said the same.

It’s possible that the reason more older Democrats prioritize choosing a candidate who can win in the general election is that they have lived through other administrations and have seen how they’ve governed, according to Rey Junco, a senior researcher at the Center for Information and Research on Civic Learning and Engagement. Junco said older Americans could be “more concerned about the autocratic tendencies in the current administration” than younger Americans, and as a result want a candidate that has the best chance of winning in 2020.

But by prioritizing electability, older Democrats may wind up backing a candidate with a major weakness: an inability to drive youth turnout. While younger voters tend to lean heavily Democratic — in 2016, for instance, they backed Hillary Clinton by around 20 percentage points — the challenge has always been getting them to the polls. But when they do mobilize, younger voters can have a profound impact on the election. The blue wave of 2018, for example, was powered in part by Gen Z, Millennial and Gen X voters, who cast more votes than Baby Boomers and people from older generations, according to the Pew Research Center.

In addition, a CIRCLE report that looked at youth voting patterns in three key battleground races in 2018 found that support for Democratic candidates was higher in counties with a high youth population in all three races. Researchers found that in the Montana Senate race, Sen. Jon Tester’s big margins in youth-heavy counties were decisive in his narrow victory. In counties with a low youth population, Tester won just 31.8 percent of the vote, but in counties with a high youth population, he won 52 percent. Strong Democratic support in counties with a high youth population also helped make the Georgia gubernatorial race and the Texas Senate race close, though both those Democratic candidates ultimately lost. According to Junco, politicians have taken note of the impact that young voters can have on close races and they may be adjusting their campaigns accordingly.

“I think you’re seeing candidates and campaigns take notice [of younger voters] in a way that they haven’t in more recent cycles,” Junco said, “And I think that you’re going to see that [form] a positive feedback loop.”

So what might this mean for 2020? It’s still early, but Sen. Bernie Sanders — who won more votes from people under 30 in 2016 primaries than Trump and Clinton combined, according to a CIRCLE analysis of 21 states — is currently leading in the polls among younger voters, with 22 percent of Democrats under 50 saying they would vote for him if the primary was held today, according to a Quinnipiac poll. But three other candidates were close behind, with Biden at 17 percent, Warren at 14 percent, and Harris at 12 percent.

Only time will tell whether younger voters continue to prioritize candidates that align more closely with them on policy issues over candidates they think can win the general election. But, for candidates hoping to win over younger voters, taking clear stances on specific policies may be the way to go. “I think there are going to be a number of issues, a number of battles being fought — especially among this generation — that reflects the nuanced nature of the young voter,” said Richard Sweeney, a 20-year-old and the chair of the Harvard Public Opinion Project, which polls adults under 30 twice a year. But Sweeney cautioned that young voters are not a monolith. “We don’t have homogenous views on all these issues. We care about a variety of substantive issues, and we have nuanced views of those issues.”

So while there may not be an easy way to do it, if any 2020 candidates do manage to get young people excited, they could use that voter bloc to argue that they’re the most electable candidate of them all.