(AP Photo/J. David Ake)

Bernie Sanders could of course win the Democratic presidential nomination, but even if he doesn’t, he has already succeeded in one crucial respect: Sanders is all but certain to exert major influence at the Democratic convention later this year, and may remain a powerhouse among Democrats for at least the near future.

A new report from a group that promotes civic engagement among young people helps underscore why: it finds that young voters could be pivotal to the outcomes in a number of presidential swing states this fall. Sanders has already shown that he has the key to unlocking young voters’ engagement in the political process in a way Hillary Clinton does not, which may ensure him a crucial, influential role in this fall’s election and beyond.

The report, from the Center for Information and Research on Civic Learning and Engagement, or CIRCLE, looks at a variety of metrics for determining the importance of the youth vote in the 2016 elections. The short version of its findings, which are based on data from the U.S. Census Bureau, exit polls, and other sources, is that young voters have the best chance to swing the presidential election in five states — Iowa, New Hampshire, Pennsylvania, Ohio, and Colorado. At least one fifth of eligible voters in each state is under age 30, and they stand out for a variety of factors, from general competitiveness to divergent support from their elders.

“If Clinton wins the Democratic nomination, her chances will hinge on the youth vote, especially in states that we have identified as the most significant for young voters,” Peter Levine, the Associate Dean for Research at Tufts’ Tisch College, which houses the CIRCLE program, tells me. “So far, she has performed strikingly poorly among young voters. She will not be able to win the general election unless she can persuade the young Sanders voters to support her in November.”

Exit polls in both Iowa and New Hampshire showed Sanders running up huge margins against Clinton among voters under 30. National polls have shown Sanders with a huge lead among young voters. While none of this proves Clinton would struggle to energize and win them over as the nominee, it raises questions as to whether that might happen. Even some veteran Dem pollsters, such as Stan Greenberg, have warned that Clinton may have to do extra work on this front.

Clinton seems to know this. In her New Hampshire concession speech, she allowed: “I know I have some work to do, particularly with young people.” But should Clinton win the nomination, that work will be twofold: Clinton will not only try to beat the GOP nominee by sizable margins among young voters; she will also try to maximize turnout among these voters, a group that historically isn’t always known for turning out.

That’s where Sanders may play a role. My Post colleague Erik Wemple flags an important quote from Rachel Maddow that brought a personal note to describing what Sanders has been able to accomplish:

“I was 19 in 1992 when Bill Clinton was running on the Democratic side, and at the 1992 Republican convention Pat Buchanan got up there and gave his ‘culture wars’ speech where he basically declared a crusade against minorities and particularly against gay people. And as a gay person watching that in 1992, I didn’t feel like Bill Clinton had my back, right? I didn’t feel like the Democratic Party had my back. He was talking about agreeing with Ronald Reagan that government was the problem and all that stuff.

“If you are a liberal, you are not a majority in this country and you know it, and it always feels that way. But this Democratic race with Hillary Clinton and Bernie Sanders campaigning this way against each other — that happened because Bernie Sanders got into this race. And all these kids who are enthused about this race — whether or not they’re supporting Bernie Sanders directly — are never going to feel like mainstream politics isn’t about them.”

This is crucial. Sanders may be making young voters feel as if they have a stake in our politics — many no doubt for the first time in their lives. This is likely in part due to his proposals, such as his climate agenda and plan for universally free public college. But it may also be due to a message that, in unflinchingly describing our challenges in monumental and urgent terms, also conveys an understanding that it is their future that is in peril.

Though there is some anecdotal evidence that Clinton, too, is engaging her younger supporters, the numbers suggest Sanders is doing this to a much greater degree. And if Clinton does win the nomination, it may come after a months-long battle that wends its way through many states, since Sanders has shown he has the capacity to rake in the money to make this happen.

By then, Sanders may well have captivated and engaged a very large national constituency of young voters. Even if he doesn’t win the nomination, Democrats will need those voters to remain engaged. That means, as David Axelrod put it recently, that Sanders “will be able to go to the convention with a lot of leverage.”

This goes beyond 2016, too. “The path back to power for the Democrats in the years ahead runs through the Millennial generation, the largest generation in American history,” Democratic strategist Simon Rosenberg tells me. “All Democrats have a lot to learn from Sanders.”

It’s a surprising twist that a 74-year-old, wild-haired career pol with an old-fashioned New York accent is the one who may have discovered the key to getting young voters engaged in the post-Obama era. But he may be playing a key role in kick-starting a process that could matter a great deal over the long term.