As March draws to a close and April opens, front runners (in the form of Hillary Clinton and Donald Trump) have emerged in the presidential primaries and caucuses that are being conducted by both of the two major parties. Those results are revealing for what they say about religiosity in modern American presidential politics.
Let's start first with the Democrats. By the time of the first major electoral contest (the Iowa caucuses), the field had been winnowed essentially to a choice between former U.S. Senator from New York and former U.S. Secretary of State Hillary Clinton, and U.S. Senator Bernie Sanders of Vermont. Beginning with the results of those caucuses on February 1st through the end of March, Clinton emerged as the heavy favorite to win the Democratic presidential nomination. In so doing, she has been helped by her moderate religiosity, which poses a significant contrast with Sanders' secularism.
Hillary Clinton grew up in the Methodist Church, attending one close to her home in Park Ridge, Illinois, a Chicago suburb. While seemingly never very religious, Hillary Rodham as she was then, belonged throughout her childhood. She has fond memories of a youth pastor who exposed her to new ideas about social justice (he took her to hear the Reverend Martin Luther King, Jr. when he came to Chicago to speak and preach). Theological moderation was the norm in the 1950's and early to middle 1960's, when Hillary Clinton was growing up, and her relationship with religion reflects that. It has clearly been a constant source of values for her, but never the central thing in her life.
That helped her, in Iowa especially, where she proudly proclaimed toward the end of a very tough caucus campaign that "I am a Methodist," something that resonated strongly with churchgoing, moderately religious Democrats, of whom there are many in Iowa. Shortly after her narrow victory there, Hillary Clinton opened up to reporters about her faith, saying that she has a group of faith advisers who "who are close to me" and also said that "I get a a scripture lesson every morning from a minister that I have a really close personal relationship with." Clinton also revealed that she has friends who are rabbis "who send me notes, [and] give me readings that are going to be discussed at services."
The contrast with Bernie Sanders is clear. He went to Hebrew School as a child, which made him familiar with the Jewish religious tradition, but he never became religious himself. Sanders' brother likes to say that "Bernie is completely secular," and Bernie doesn't disagree with that assessment. Instead, he says that certain parts of the Jewish religion inform his secular quest for social justice.
Consider now, the Republican side of the presidential nomination process this year with respect to the issue of religiosity. By the end of March, Donald Trump had emerged as the GOP front runner. Trump's connection to religion remains somewhat murky. He claims to have belonged to New York's Marble Collegiate Church as a child, which was a place of note (the famed clergyman and theologian Norman Vincent Peale was the senior minister there for many years). But there is no record of Trump having been a member there then. More likely, he and his family went to services at Marble Collegiate, but never actually joined. Trump considers himself a Presbyterian, but seemingly in a fairly nominal sense. Like Hillary Clinton, his contemporary, Trump grew up in an era that tended to bring even the not-all-that-religious to church, at least once in a while, and that seems to be what he was like then.
Trump's efforts on the campaign trail to sound familiar with scripture are awkward and unconvincing, but they succeed in reassuring voters that he does at least consider himself to be a Christian, in some minimal sense. That has helped Trump perform better in the GOP nominating process thus far than strongly religious candidates such as Texas Senator Ted Cruz and Dr. Ben Carson. For Cruz and Carson especially, religion has clearly been the central thing in their lives; both men can fairly be described as very religious. But many GOP primary voters and caucus participants are clearly uncomfortable with a very religious person as a candidate for President. "Religious yes, but not overly so" appears to be the most appealing version of religiosity within today's GOP presidential primary and caucus electorate.
And so even though the two major parties are very different in some ways, this year they have tended to behave more alike than differently with respect to what is most electorally appealing in terms of religiosity in a presidential candidate. That fits with a longer-term pattern in American presidential politics, which tends to screen out both the most secular and the most religious.