Over the last few weeks, a couple of Wall Street Journal reporters did what any smart political journalist should be doing in the run-up to a presidential campaign. They dialed up all 99 Democratic Party county leaders in Iowa, and quizzed them on the emerging field of 2020 candidates. It was a valuable exercise: with our elite political conversation ever more narrowed by the distorted reality of Twitter, outside-the-Beltway voices remain depressingly hard to to find in mainstream political news. Party activists like those in Iowa, the first state to vote come 2020, still matter. Not because they wield the same kind of grassroots influence that they used to, but because they’re just earnest, highly engaged voters in what might be the country’s most important political state. They pay close attention to politics without being jaded. Their opinions tell us more about the Democratic psyche than any current poll of the 2020 race can.

What did the Journal team find? The biggest emerging divide in the early field was not about ideology or race or anything directly related to President Donald Trump. The overwhelming takeaway was that Democrats want generational change. It was bad news for the three Democrats already seen as front-runners for the nomination: Bernie Sanders (age 77), Joe Biden (76), and Elizabeth Warren (69). The same can be said of former New York City mayor Michael Bloomberg, age 76, who toured Iowa on Tuesday as he ponders a White House bid.

“They’re all too old,” Chris Henning, the 71-year-old Democratic chairwoman in Greene County, told the Journal. “It’s not white-bread America anymore; we’ve got to get with the program.”

Read that quote again, and the person who said it. Even the olds don’t want the olds to run for president!

It’s a lesson borne out by the midterm elections, which saw a new generation of Democrats sweep into power, thanks in part to the highest turnout among young voters in a quarter century. An estimated 31 percent of eligible 18- to 29-year-olds cast ballots in 2018, and they broke for Democrats nationwide by a 31-point margin. The three splashiest Democrats on statewide ballots—Andrew Gillum in Florida (age 39), Beto O’Rourke in Texas (46), and Stacey Abrams in Georgia (44)—all narrowly lost. But among millennials, these young candidates crushed. In O’Rourke’s case, he beat Ted Cruz by a head-exploding 42-point margin among under-30 voters. It was a clear marker that new faces and innovative campaigns can deliver big results for Democrats as they look to the future.

But the changing face of Democratic politics is perhaps better reflected by the new House members who won last month, and not just because young people voted for them. Older people did, too. There are now 18 Democratic members of Congress under the age of 40, including 29-year-old Alexandria Ocasio-Cortez, 29-year-old Abby Finkenauer, and and 31-year-old Katie Hill of California. All of them were toddlers when the Berlin Wall fell, all of them were in middle school when 9/11 happened, and all of them were raised in a world connected by the Internet. This is a good thing, because they understand more about the country as it is now better than most of the people tasked with running it. If you don’t believe that, then you have a warm seat waiting for you on the Senate committee that didn’t know how to ask Mark Zuckerberg a single valuable question about technology when he testified on Capitol Hill.

Millennials are now the largest voting-age generation in the country, the biggest chunk of the U.S. labor force, the dominant taste-makers in our popular culture. They are not the caricature that has emerged online, painting them as woke avocado-eaters who tweet about intersectionality and Lena Dunham’s woebegone rescue dog. Yes, millennials are hardwired into the Internet and spend a lot of time on their phones. But many millennials are about to turn 40. They are Republicans and Democrats. They have kids, they live in the suburbs, and they listen to dad rock as much as they listen to Beyoncé. They are black and brown and white. They fight our endless wars, they belong to labor unions, they’re saddled with student-loan debt so crippling that an entire generation has to think twice before buying a sensible hybrid at CarMax, let alone a whole house like their parents. And they firmly believe that the vocabulary of politics is completely detached from their experience, which is now the lived reality of the American majority. It’s why Democrats in 2020 need to think carefully before nominating a standard-bearer who even comes close to approaching the same age as Trump (72).

Successful presidential campaigns work when they offer a clear choice rather than a mushy alternative. That choice, articulated correctly, is performed through both policy and style. The last two Democrats to occupy the White House won because they presented a blunt contrast to their Republican opponents. Bill Clinton won in 1992 not just because he was able to “feel your pain” at a time of economic worry, but also because his relative youth and cultural literacy allowed him to create talkable moments—playing the saxophone on The Arsenio Hall Show and doing an interview on MTV—when cable television was becoming ascendant. Barack Obama bested John McCain not because he tapped so potently into online organizing and fund-raising, though that helped, but because of the 2008 economic collapse and the deep unpopularity of the outgoing Republican president. It didn’t go unnoticed, though, that Obama liked Jay-Z and knew how to pay his cable bill online, while McCain told people he was “an illiterate that has to rely on my wife” for the Internet. The former was relatable, the latter was decidedly not.

In 2020, in a fight against Trump, the style contrast becomes even more critical than it was for Clinton or Obama. On policy today, whether it’s health care, immigration, or guns, Democrats today are largely unified. There may be strong differences in the 2020 primary about abolishing ICE or delivering free college education—more on that later—but the kind of ideological debates that flared in the 2016 primary between Sanders and Hillary Clinton seem less explosive now. Whoever emerges from the primary, whether it’s Kamala Harris or an augmented-reality Bitmoji version of Michael Avenatti pegged to the five minutes last year when people actually like Michael Avenatti, the midterms plainly showed that Democrats will show up to vote for anyone with a D next to their name, no matter the policy platform that lives on their campaign Web site. The choice in the Democratic primary ultimately is about only one thing: who is best prepared to beat Trump at a time when Trump owns the culture? Someone who actually understands culture would be a start.

“If we think about American politics as dramatically polarized and tribal, and you look for ways to puncture the tribal nature of it, I think youth and cultural currency is a significant way of puncturing it against Trump,” said Nicco Mele, director of the Shorenstein Center on Media, Politics, and Public Policy at the Harvard Kennedy School. Clinton and Obama did not become presidents because they were younger than their aging Republican opponents. That they looked fresh and different was part of it. But their youth, and their attendant instincts, allowed them to plug into mass culture at a time when voters wanted change. Both won because they were able to command the most prized commodity in politics: attention. They were new, and the political media in particular has always been obsessed with new.

Trump, in spite of his age and his long made-in-China neckties, won in much the same way: because he understood that profit-driven news operates in fundamentally the same ways as profit-driven entertainment. Trump, too, had been living on Twitter since 2009, and his birther crusade showed that he could surf the dumb outrage culture of social media right into prime-time TV bookings as media executives happily watched their sales revenue climb. On Twitter, he learned something valuable that many politicians are still slow to pick up on: that the language of the Internet is not distinct from real life. It is the same. There are no offline lives. Even people who choose to “unplug” from the world and live in retrofitted camper vans still post about it on Instagram. Democrats who understand a simple fact about American life now, that millennial culture is actually just culture, will thrive in the primary and beyond.

“Pre-Internet culture was already about celebrity,” Mele told me. “And that began to infect the news media with cable news. Journalism gets that bug, and then the Internet shows up. In that stew, of course Trump wins. So you look at 2020, and you think: how do you defeat this celebrity in this culture? The answer is you make him look old and foolish and stupid and lame. Maybe you do it with a comparable celebrity. You do it, though, by tapping into a language that is far outside the political establishment, but is actually the language of the culture.”

Already, some Democrats have tried to do this and whiffed. As Warren learned this year, getting into a hot-button debate on social media with Trump is a perilous exercise. It’s a battle conducted entirely on his terms, and the personality contrast that matters so much in campaign politics quickly evaporates. Trump always wins that fight. This doesn’t mean that the 2020 candidates should avoid talking about Trump online. That would be silly: Americans today spent an average of six hours a day with digital media, and almost four hours with television media, according to eMarketer. It means that Democrats have to find ways to capture attention across these screens, on their own terms, without succumbing to the traps that Trump lays.

The best current practitioner of this behavior is Ocasio-Cortez, who is not running for president. But she is already more famous than pretty much every other member of Congress and several presidential candidates. Yes, that’s owed to her upset victory over Rep. Joe Crowley earlier this year, and the creeping influence of the Democratic Socialists on the left. But it’s also due to the fact that she, an attention-merchant like Trump, understands that social media is the most powerful way to both create a narrative and influence the media. Ocasio-Cortez uses her tweets and Instagram posts to rally support for her causes, to give voters an authentic behind-the-scenes look at her life, and to punch down at buffoonish right-wing targets, endearing her even more to her supporters. Social media amplifies her uncanny ability to get under the skin of conservatives and rile up the frustrated beta males of Fox News. By being herself online, she both creates and controls her own powerful feedback loop of media coverage, without being drawn into fights she doesn’t want. Much like the Marjory Stoneman Douglas High School shooting survivors, who used Twitter to go after powerful interests and politicians, Ocasio-Cortez is a dominant communicator on social media, simply because she grew up with social media. It is her native tongue. Who needs a press release?

In 2020 primaries, the candidates who don’t overthink social media—the ones who use it because they like it, not because they have to—will be powerfully rewarded. Looking at the early presidential field, there only seem to be a handful of potential candidates who naturally understand the language of the Internet. O’Rourke is certainly one. Cory Booker is another. Tulsi Gabbard and Eric Swalwell, both members of Congress, are also phone-first politicians. All of them are under 50.

Winning is about much more than just utilizing technology, of course. A candidate must offer a choice in vision—a vision that feels big enough to bend the culture. And while policy fights may end up being more muted than they were in 2016, arguments over vision might not be. The case for competence could be a potent message, and that’s certainly the pitch Democrats would hear from Biden, Bloomberg, or perhaps from former and current mayors Mitch Landrieu and Eric Garcetti. Or maybe there’s the argument that quiet, across-the-aisle hard work is what we need after Trump—that seems to be the Amy Klobuchar argument, if there is one. These are valid cases to be made. But they are not terribly electrifying. It’s hard to envision LeBron James wearing a Bloomberg hat when he arrives at Madison Square Garden to play the Knicks next year.

Another kind of debate simmering underneath the Democratic race is about identity. African-Americans have enormous sway in the primaries, especially in an early swath of Southern contests. Can a white man win over black voters against African-American candidates? Can a black candidate win over working-class whites in the general? These debates are often oversimplified, but they are thorny. What’s potent about a generational argument is that is has the potential to supersede many of these divisions.

“The Democratic Party is dispositionally more inclined to support young people stepping forward. It’s a general trait that we have,” said Pete Buttigieg, the Democratic mayor of South Bend, Indiana. He’s also laying the groundwork for a presidential campaign. Buttigieg is not quite a larger-than-life figure, but he is 36 years old, a Rhodes scholar, a veteran of the war in Afghanistan, and the first openly gay elected executive official in Indiana. “One thing I noticed, running for mayor in my twenties: your face is your message,” Buttigieg told me. “Just the fact that you’re running. A young person running for office is an act of hope. And I think hope versus fear is going to be the framework for this election.”

With a newly activated generation of voters, he said, the issue set is often at odds with what people in Washington think it is. It demands a message that can tap into the deep unease young Americans feel. Democrats have to address the fact that people under 40 see the country in different terms than the Baby Boomers who inhabit our corridors of power and tune in to God Friended Me on Sunday nights.

“If you are planning to be alive in 2050, the world looks different to you, and your priorities are different,” Buttigieg said. “If you are in my generation or younger, you are the generation that experienced school shootings beginning when I was in high school, the generation that fought in most of the post 9/11 wars, the first generation to have to deal with the reality of climate change, the first generation not to be better off than our parents materially—if nothing changes. For us, I think there is a little less tolerance for abstention. We care about abstraction and broad themes, but what are you going to do about it?”

Like the debate over identity, the case for a next-generation candidate is not tidy. O’Rourke, arguably the most popular Democrat in the country across age groups and social platforms, seems to have the best claim to that argument at the moment. No one in Democratic politics has a better hold on the imagination of millennials. But structural advantages in the primary might favor Harris or Booker, who are both African-American, but also decades younger than Biden or Sanders. As for Biden, he’s old, but thanks to the Onion and his Uncle Joe persona, he’s already optimized for meme culture.

Sanders, in the 2016 context at least, also scrambles the hypothesis. Even as a cranky septuagenarian, he won over legions of young people and became a pop-culture icon, the cool progressive grandpa painted onto untold graffiti murals and bespoke Etsy products four years ago. He still churns out an avalanche of his own produced content, and distributes it across platforms in a way that laps most of his fellow Democrats. But it’s hard to run for president twice and still lay claim to the mantle of change that those Iowa activists are screaming out for. Especially when you’re no longer just running in a head-to-head race against someone like Hillary Clinton, who painfully urged young people to “Pokémon Go . . . to the polls.”

This is not 2016. Every primary has a different chemistry that shapes messages and candidates and voter responses. But it’s always valuable to look back in order to look to the future. And the last two times Democrats won the White House, they did so by making room for the young person coming up from behind.

Bryce Smith, the 26-year old chairman of the Dallas County Democratic Party in Iowa, told the Journal the same thing. “We have to look for the Barack Obama scenario for the part. I can’t see how my generation, 18- to 34-year-olds, can get excited about a 70-year-old candidate ever again.”

Peter Hamby is the host of Snapchat’s Good Luck America.

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