That might not matter in the bluest parts of the bluest states, said Mike McCurry, a Democratic consultant who served as the White House press secretary under President Bill Clinton and now teaches at the Wesley Theological Seminary in Washington. But, he added, “I sure as hell believe that it would work in Michigan, Wisconsin and Pennsylvania, and that’s what it’s all going to come down to.”

The church-state divide shouldn’t dissuade the candidates, McCurry told me. “That’s such a misreading of what the political DNA of America is,” he said. “We have had religion woven into our political structures and our political debate from the very beginning.”

Besides, he added, a Democrat who speaks persuasively about religion has a potentially huge tactical advantage: “Think ahead to the general election. If you’re talking about faith in an authentic, genuine way, imagine the contrast if you’re running against Donald Trump, who has absolutely none of that vocabulary.” While the president may have the farthest reaches of the religious right locked down, many Americans of faith are appalled by him.

And he’s vulnerable not just because of his personal history and public demeanor, which amount to a raging bonfire of the pieties. He also has governed in ways that contradict the principles of charity and mercy that are central to many religions.

Pete Buttigieg took gorgeously effective note of this in the Democrats’ first debate, in June, referring to the Trump administration’s treatment of migrants at the border.

“The Republican Party likes to cloak itself in the language of religion,” he observed. “But we should call out hypocrisy when we see it.” And any political party that suggests that “God would smile on the division of families at the hands of federal agents — that God would condone putting children in cages — has lost all claim to ever use religious language again.”

Buttigieg, a churchgoing Episcopalian, refuses to cede religion to Republicans or let them use it as some crude moral cudgel. He weaves it into discussions of his marriage to another man. “Nothing has made me feel more connected, more able to be true, however imperfectly, to my faith than the experience of putting myself second,” he said at a CNN town hall this month. “That came with committing my life to my husband, Chasten.”