Last September, Bernie Sanders arrived at Liberty University, in Virginia, to give a major speech about religion, faith, and the moral bankruptcy of the American economy. For 27 minutes, Sanders delivered a stump-speech-turned-sermon on economic justice. He quoted the Gospel of Matthew. He quoted the pope. He quoted a passage from the Book of Amos that’s extremely popular among liberal American Jews (“Let justice roll on like a river…”). He asked his audience to help him build “a moral and just society.”

It was surreal political theater. Sanders, a Jewish socialist, was preaching to 12,000 conservative evangelical Christians. And he was doing it on the morning of Rosh Hashanah.

At the time, few reporters commented on the timing of the speech. Most focused on the choice of venue; democratic socialist senators from Vermont don’t usually speak at ultra-conservative Liberty University’s morning convocation service. But there it was: the first-ever Jew to make a serious run for the presidency, skipping synagogue on one of the holiest days of the Jewish calendar, in order to show an evangelical audience that his candidacy would be more morally charged, more concerned with issues of justice, and more frank about prophetic themes than almost any other campaign in the modern era.

It’s unlikely that Sanders went to Liberty hoping to win over conservative evangelical Christians. His message that morning was intended for the progressive left, and it seemed to be something like this: We’re going to reclaim the mantle of values-and-morals politics from the Christian right. And we’re going to do it not by embracing organized religion, but by being more secular than anyone else.

Intentional or not, that’s the religious message of the Sanders campaign. Already, the outcome has been historic: With his primary win in New Hampshire last month, the Vermont senator became the first non-Christian politician, in either party, to win a presidential primary.

And if Sanders’ success among young progressives is any indicator, that values-driven message might be perfectly tailored to an era of religious disaffiliation—one in which more people are uncoupling their moral search from the institutions and authorities that defined American religious publics of eras past. Like a growing number of Americans, Sanders does not define himself within clear religious categories, even as he stays engaged with questions of morality and a just society.

Sanders speaks largely in a key of moral outrage. Billionaires and super-PACs figure prominently in his demonology. Not one for understatement, he describes inequality as “the great moral issue of our time.” This trait can make some spectators on the left dream of Jeremiah. When I interviewed the Christian novelist and essayist Marilynne Robinson for Salon last November, she told me that Sanders “preaches, and he understands the burden of prophecy.”

“Unlike his slicker rivals, Sanders is most at ease talking about the moral and ethical dimensions of politics,” wrote Margaret Talbot in a New Yorker profile headlined “The Populist Prophet.”

At the same time, Sanders has been frank about his lack of interest in formal expressions of piety. “I am not actively involved with organized religion,” he told The Washington Post a few weeks ago. Unless prompted, he virtually never brings up scripture or Judaism. Last October, when Jimmy Kimmel asked Sanders if he believed in God, the candidate’s answer was so vague that it seemed Americans were about to get their first openly atheist national politician. Since then, Sanders has said that he’s a believer. When an interviewer from Rolling Stone asked Sanders if he believed in God, the candidate said he did, and at a town hall meeting in New Jersey in February, Sanders explained that “I would not be running for president of the United States if I did not have very strong religious and spiritual feelings.” But Sanders uses terms to describe his fundamental beliefs (“all of us are connected”; “we are all united in one way or another”) that are universalistic enough to encompass most Americans—including many who do not believe in God.

When Sanders does talk about Judaism, it’s usually to express cultural pride, or to explain how the rise of the Nazis—who murdered much of Sanders’ father’s family—pushed him to recognize the high stakes of politics. Personal practice, specific observances, and detailed beliefs just don’t figure in to Sanders’ campaign rhetoric.

A secular streak does not, by itself, make Sanders unique among American political figures. Since Thomas Jefferson, the country has had irreligious leaders. Dwight Eisenhower, our country’s most Leave It To Beaver president, didn’t affiliate with a religious group until after he became president. In an interview, Princeton historian Kevin Kruse suggested that Sanders’ closest analogue is 1988 Democratic nominee Michael Dukakis, a nominal Greek Orthodox Christian who, like Sanders, spoke about religion largely in terms of his family’s immigrant experience. “There’s a sense in which more intellectual candidates on the left shy away from faith,” Kruse said. “In that way Sanders is nothing new.”

Polls consistently find that a majority of Republicans and more than 40 percent of Democrats say that they would be less likely to vote for an atheist candidate. But it’s a mistake to assume that what people say about a hypothetical candidate will actually apply when faced with a breathing, branded human politician. If the 2016 election provides any kind of evidence, it’s that the electorate is more open to impiety than it admits to pollsters. Donald Trump, the Republican frontrunner, clearly has not spent much time in church. Few of his supporters seem to believe his claims to a deep Presbyterian faith. Nevertheless, he has made a strong showing among white evangelicals.

If Sanders is unique, it’s in catering to a base—young, white urban progressives—whose ambivalence toward organized religion seems to match his own. What’s significant about Sanders, Kruse argues, is that he’s making this pitch at a time when a surging number of Americans identify as either having no religion or as being spiritual but not religious. These so-called “nones” form a fluid polling category, and their numbers are difficult to pin down. But one widely cited study put them at around 20 percent of the U.S. adult population.

Sanders “mirrors where it’s going in America,” said Kaya Oakes, author of The Nones Are Alright, a book about young, religiously unaffiliated Americans. “Younger people are moving away from this strict, you can only belong to one religion [approach], to this sort of syncretism and DIY religion and choosing beliefs and combining them. He absolutely is a product of the time that we’re in.”

But it’s important to realize that Sanders’ flavor of secularity may not primarily be about religion, or irreligion, at all. If anything, it seems to be part of a larger rejection of personal narrative and identity politics. Sanders has not just skirted the campaign tradition of religious testimony—he has largely avoided an entire style of politics that’s predicated on personal testimony.

In presidential politics, candidates position themselves not simply as representatives of their platforms, but as embodiments of particular kinds of American narratives, and of particular kinds of American futures. Barack Obama mastered this form in 2008, when he presented his life story as evidence—as testimony—to the narrative that he wished to pitch, which was that of a country progressing toward new forms of opportunity and unity. In a more modest form, Clinton, Cruz, Trump, and Marco Rubio have all positioned themselves as physical representations of an American dream.

This is embodiment politics, and it’s tied up with transcendent visions of American history and destiny. As Clinton put it in her campaign launch speech last year, after extensive discussion of her mother’s hard life: “Here, on Roosevelt Island, I believe we have a continuing rendezvous with destiny. Each American and the country we cherish.”

Sanders actually has a nice, sellable, rags-to-riches story: He grew up in a working class family in Brooklyn, and went on to attend an elite college; his father was an immigrant, and his mother the daughter of immigrants; as a Jew, he has access to a particular kind of outsider narrative. Sanders does reference this story, but only briefly. When he plays identity politics at all, it’s in reference to economic class—I, too, the message goes, have seen economic scarcity. Otherwise, with a smattering of exceptions, he has made it a point, at times explicitly, to remove the personal from his politics.

As a result, Bernie Sanders’ campaign seems immanent in two senses: first, he does not give scriptural stories special moral authority. And, second, he does not give his own story special moral authority.

You could see this attitude on display in the first Democratic presidential debate, when the then-five candidates got up to give their introductory speeches. The other four talked about their resumes, their grandchildren, their personal stories. They said nice, normal, getting-to-know you things, such as “I’m Hillary Clinton” or “My name is Martin O’Malley,” or “My mother grew up in the poverty of east Arkansas, chopping cotton.” Sanders thanked the moderator. Then he pivoted to his favorite register, rage. “I think most Americans understand that our country today faces a series of unprecedented crises,” Sanders began. In his choreographed introduction to the American people, he did not bother to say his own name.

Something about this approach feels very Jewish. In part, it may be a relic of a history in which Jewish identity was often a barrier to social and political power. The solution was to conceal that identity—or to demand access based on less personal or tribal qualities. “I think Jews in this country know that the less that we are judging people on the basis of their beliefs, their ethnic heritage, how they worship or don’t worship, how they believe or don’t believe, the better the country will be,” said Jeffrey Falick, the secular humanistic rabbi at Birmingham Temple, the country’s oldest congregation of secular humanist Jews. “And I think that comes from the Jewish experience,” Falick added.

Alternately, this approach may feel so Jewish simply because the alternative feels so Christian. In contrast to the campaigning-as-testifying model, Sanders offers a kind of secular prophetic style, in the spirit of the Hebrew Bible—one in which the messenger matters much less than the message, and in which the appeal is not to some higher authority, but to the basic moral faculty of human beings, which is to say, our sense of fairness. Some people have a lot of money. Many more have very little. Cue the social critique.

You may agree with that critique—or not—and you may agree with Sanders’ proposed solution to the problem—or not—but one thing is clear: in the America of 2016, this message has legs. Sanders probably won’t win, but against all odds, he’s yet to lose. And among young progressives, he’s beating Clinton by massive margins, winning more than 80 percent of the 18-29 year-old Democratic vote in Iowa, New Hampshire, and Michigan.

There is a tendency to view religiously unaffiliated Americans—the nones—as simple dropouts from spiritual life. There’s no evidence that this is the case. The nones are little more than a polling category, and they represent a diverse slice of people, including atheists and believers. One study found that as many as 30 percent of them re-affiliate with a religious group within a year.

When I spoke with Oakes, the Nones Are Alright author, she suggested that the appeal of a candidate like Sanders, and the turning away from organized religion, might share a common root in the suspicion of authoritarian structures. “Nones aren’t attracted to top-down forms of religion” where “there’s an authority figure at the top who tells everybody else what to do,” Oakes argued. She speculated that this suspicion of authority might drive the rise of leaderless movements, such as Occupy, as well as the appeal of a candidate like Sanders.

What politicians and religious denominations have in common is the assertion that the messenger certifies the message—that the imprimatur of a leader makes a particular platform legitimate. In an age of mass culture and celebrity, the awkward, private, de-testimonied, disorganized specter of Sanders suggests the opposite. That which makes a message seem authentic may be its delivery by the unlikeliest of messengers.

Michael Schulson is a freelance journalist and an associate editor at Religion Dispatches magazine, where he co-produces The Cubit.