Why millennials back Sanders – and why Clinton can win anyway

Why is a 74-year-old white socialist Jew so popular with young voters?

That is, essentially, the opening question Stephen Colbert asked Vermont Sen. Bernie Sanders on the Late Show Wednesday night.

The Democratic candidate barely skipped a beat.

“By definition, young people are idealistic, and they look at a world with so many problems and they say, why not? Why can’t all people in this country have healthcare? Why can’t we make public colleges and universities tuition-free?" Senator Sanders said. "[Young voters are] not dumb, and they’re saying hey, we want a fair shake as well.”

The exchange highlights one of the defining distinctions in the 2016 Democratic nominating race: The large age gap between Sanders and Clinton supporters, a "Grand Canyon-sized chasm" that helped Sanders win New Hampshire – and that threatens to handicap former Secretary of State Hillary Clinton in contests to come. 

Some 86 percent of voters aged 18 to 24 chose Sanders in New Hampshire's primary, according to exit polls. Sanders also won 78 percent of first-time voters. The only age demographic Mrs. Clinton won? People 65 and older.

Iowa saw a similar breakdown; Sanders defeated Clinton among voters ages 17 to 29 by 70 percentage points.

Even Clinton admits the age gap is "amazing."

"I know I have some work to do, particularly with young people," she said in her New Hampshire concession speech. "But I will repeat again what I have said this week: Even if they are not supporting me now, I support them."

And with good reason: she doesn't want to repeat the past. In 2008, Clinton lost young voters to Barack Obama by 46 points.

It appears millennials are abandoning Clinton again. Like Taylor Gipple, a young voter who asked Clinton her first question in an ABC News town hall debate Jan. 25, just before the Iowa caucuses.

"It feels like there are a lot of young people, like myself, who are very passionate supporters of Bernie Sanders and I just don't see the same enthusiasm from younger people for you. In fact, I've heard from quite a few people my age that they think you're dishonest but I'd like to hear from you on why you think the enthusiasm isn't there," he asked.

Clinton, whose response was less memorable than the stinging question, is trying to stanch the millennial exodus. But Sanders appears to be meeting her at every turn.

She's proposed a "College Compact," which would allow students to attend college without taking on debt. Sanders has countered with tuition-free college.

She's proposed a $12 per hour minimum wage. Sanders is pushing for a $15 per hour minimum wage.

She's pledged to keep Obamacare. Sanders wants to roll out free, comprehensive, universal healthcare.

Clinton is active on Facebook, Twitter, and even Snapchat, where she snaps about Planned Parenthood and other issues important to young voters. So does Sanders.

The Clinton campaign has also trumpeted endorsements from young celebrities – like Lena Dunham, Christina Aguilera and America Ferrera – to court millennials. So has Sanders, whose list of celebrity supporters includes Will Ferrell, Jeremy Piven, and Sarah Silverman.

Despite Clinton's efforts, young voters still back Sanders by large margins, and in media reports, they cite the same trait for their support of the self-described Democratic socialist.

Wild-haired, slightly disheveled, impassioned and un-apologetic, Sanders seems "genuine," "sincere." Clinton, polished and poised, is "too cozy with the establishment," and "not trustworthy."

Despite younger voters' overwhelming support for Sanders, there's reason for Clinton to remain confident – and for Sanders to worry.

Young voters are notorious for not turning out at the polls. Across all of the 2008 Democratic party contests, voters older than 45 – Clinton's wheelhouse – cast 61 percent of Democratic votes, according to a cumulative analysis of the results of all the exit polls in the 2008 Democratic primary conducted by ABC pollster Gary Langer. Those younger than 45 – where Sanders dominates – cast only 39 percent.

As The Atlantic noted, "[W]hen it comes to piling up votes, one of these demographic advantages is much more useful than the other."