Among the biggest surprises of the Democratic presidential campaign so far are the rise of Pete Buttigieg and the resurgence of Elizabeth Warren, both of whom, according to a new Des Moines Register poll, have moved into a virtual tie for second place in Iowa with Bernie Sanders. In many ways, the Buttigieg and Warren phenomena are distinct: Buttigieg promises generational change; Warren is almost 70. Buttigieg emphasizes his success in a conservative state; Warren stresses her willingness to challenge corporate power. Buttigieg has become a darling of the big donors whom Warren eschews.

What unites them, and separates them from Sanders and Joe Biden, is their unabashed intellectualism. Both have made braininess central to their political brand. And it’s working—a fact that offers a window into the changing culture of the Democratic Party.

Warren and Buttigieg don’t showcase their smarts in exactly the same way. Warren does it with deep dives into policy: proposal after detailed proposal on subjects such as housing, climate change, child care, college tuition, and antitrust. Her campaign sells warren has a plan for that T-shirts. She talks gleefully about “nerding out” on policy, and when asked at a CNN town hall whether she preferred being a politician or a professor, she replied, “Oh, teaching, are you kidding?”

If Warren plays the brilliant professor, Buttigieg plays the brilliant student. Among the people who introduced him when he announced for president was a former teacher who began her remarks by describing how he had wowed the judges at a high-school economics competition sponsored by the Federal Reserve. Type Pete Buttigieg into Google, and one of the prompts you get is “languages.” News reports often mention that he speaks seven, and this spring a video of him speaking Norwegian went viral. In April, he filmed a video in French offering his condolences for the fire at Notre-Dame.

It’s not unusual for Democratic presidential candidates to have impressive resumes. Bill Clinton is a Rhodes Scholar; Barack Obama was the president of the Harvard Law Review. Cory Booker and Julián Castro attended Stanford; Amy Klobuchar went to Yale. In fact, every president since Ronald Reagan has been a product of the Ivy League.

What’s new is that Warren and Buttigieg are leaning into their credentialed intellectualism rather than worrying that it will make them appear elitist. That’s exactly what Clinton’s advisers feared in the summer of 1992, when the Arkansas governor was trailing both George H. W. Bush and the businessman Ross Perot, who boasted that he was assembling a team of “Road Scholars in Washington—that’s r-o-a-d scholars, the people who are street smart and have common sense.” Clinton’s advisers responded with a biographical video, titled “The Man From Hope,” which emphasized his small-town roots and avoided mentioning that he had attended Georgetown University and Oxford. In the film’s only reference to Yale Law School, Hillary Clinton notes that Bill didn’t want to serve on the school’s law review, because he was more interested in returning to Arkansas to be a “country lawyer.”

Bill Clinton’s anxiety about appearing smarter than thou seemed borne out when George W. Bush used Al Gore’s academic affectations against him in 2000. After a widely discussed New Yorker essay in which Gore confessed his fondness for Maurice Merleau-Ponty’s book Phenomenology of PerceptionTalkmagazine asked Bush to admit a weakness. He answered slyly, “Sitting down and reading a 500-page book on public policy or philosophy or something.”

A similar dynamic played out in 2004. Like Buttigieg, John Kerry speaks French. But Kerry didn’t showcase that ability while running for president. To the contrary, Republicans used his linguistic skills to undermine his Americanness. Then–House Majority Leader Tom DeLay delighted GOP audiences by beginning speeches by saying “Hello, or as John Kerry might say, ‘Bonjour.’”

Bush’s and DeLay’s attacks reflected a shift in the culture of the GOP. As late as 1994, according to the Pew Research Center, voters who had graduated from college were 15 points more likely to identify as Republicans than Democrats, and voters with graduate degrees were almost evenly split between the two parties. By 2017, college graduates’ partisan leanings had flipped: They now favored Democrats by 15 points. Among Americans with graduate degrees, the shift has been even starker. The Democratic advantage, which stood at two points in 1994, had grown to 32 points by 2017.

As a result, the educational composition of the two parties has diverged. From 1997 to 2017, the share of registered Republican voters who finished college stayed the same. Among Democrats, it rose by 15 points. This shift has influenced the way the two parties see education itself. In 2010, Democrats were seven points more likely than Republicans to say that colleges and universities have a positive effect on America. By 2017, they were 36 points more likely.

Now a decade or two after Bush and DeLay realized that anti-intellectualism mobilizes Republicans, Warren and Buttigieg have realized that intellectualism mobilizes Democrats. Unlike Biden and Sanders, they both poll significantly better among voters with college degrees, who in recent decades have grown substantially as a share of the Democratic primary electorate. Buttigieg’s reputation for detailed, thoughtful answers—as showcased in his widely hailed CNN and Fox News town-hall events—has helped elevate him above his closest generational rival, Beto O’Rourke. And Warren’s unabashed wonkery has helped her close the gap with Sanders on the party’s left flank.

Warren and Buttigieg are also likely benefiting from the contrast with Donald Trump. “Wouldn’t it be great to have a president who was really smart. I mean really, really, really smart,” declared Steve Adler, the mayor of Austin, Texas, at Buttigieg’s announcement rally. “Someone who spoke multiple languages, including having a beautiful command of English.”

If Warren or Buttigieg wins the nomination, the 2020 presidential race will feature the most profound intellectual contrast in modern American history. It’s difficult to envision a debate between Warren, who asks crowds, “Do I have any net-metering wonks out here?” and Trump, who claims that tariffs are a payment China makes into the United States Treasury. Or between Buttigieg, who speaks about John Rawls and James Joyce, and Trump, who speaks about “Two Corinthians.”

It’s likely Republicans would try to turn intellectualism into a negative for either Warren or Buttigieg. After all, the general electorate is neither as highly educated nor as favorably disposed toward higher education as Democratic primary voters. It’s a tactic that’s worked in the past. What’s harder to know is what will happen if a Democratic nominee wears these attacks as a badge of honor. To the debates over whether America is ready for a woman or a gay president, Warren and Buttigieg are adding an additional wrinkle: Is it ready for a nerd president, too?