[Read: Democrats have a religion problem]

Faith has come up often in the 2020 Democratic race so far. In her campaign-kickoff speech, Senator Kamala Harris of California nodded to the faith of abolitionist and civil-rights leaders, arguing that “to love the religion of Jesus is to hate the religion of the slave master.” Senator Elizabeth Warren of Massachusetts referred to the Book of Matthew in a CNN town-hall interview in mid-March while talking about the importance of fighting poverty. At a similar CNN event, Senator Cory Booker of New Jersey told potential voters that “Christ is the center of my life,” and quoted Jewish teachings in Hebrew.

But no one has created as much buzz about faith as Buttigieg. “As someone who comes from a religious background, is an Episcopalian, and is gay, these aren’t just theoretical issues for him,” says Michael Wear, who worked on faith issues in the Obama White House and directed faith outreach during the former president’s 2012 reelection campaign. Buttigieg has “actually had to work out in his own life how his views, how his life, enmeshes with his faith.”

Speaking the language of faith is an effective way to get media attention—Democrats’ tortured relationship with religion has long been a theme in political coverage, and faith is rightfully seen as an important factor in elections. But religious rhetoric only goes so far as a way to win votes. The more important measures of candidates’ savviness about faith and politics will be in their campaign substance and structure. “It shouldn’t just take a politician quoting Matthew 25 for you to be all in,” Wear says, referring to Warren. “You need to be paying attention to the policies … to how much of their actual time they’re spending [on] issues you care about, and [on] institutions and organizations you care about.”

This is where 2020 Democratic hopefuls may be learning from past failures. The day after Clinton conceded defeat in the 2016 election, The New York Times’ Amy Chozick reported an illuminating anecdote: Early in her campaign, Clinton had been asked to speak at a prominent St. Patrick’s Day event at the University of Notre Dame, but declined because “white Catholics were not the audience she needed to spend time reaching out to.”

Among Democratic faith advisers, this was seen as the perfect encapsulation of her campaign’s fatal mistake. Despite her personal history as a lifelong, devout Methodist, Clinton did not center her faith in her presidential bid. If “Hillary had a sophisticated, state-of-the-art outreach team on the ground in [Wisconsin, Michigan, and Pennsylvania], there were 40,000 persuadable voters who were looking for a reason not to vote for Trump from a values and religious standpoint,” says Shaun Casey, the director of Georgetown’s Berkley Center for Religion, Peace, and World Affairs and a former Obama administration official. “They never were approached in that fashion.” Faith-outreach efforts could make the difference in crowded early primaries, in which candidates are desperate to differentiate themselves, Casey says, and in the general election, when important swing states could be tipped by turnout from religious Hispanics or middle-of-the-road white Christians who might be wooed away from Trump.