If you think religion doesn't matter in politics, think again.
Religion continues to play both spoiler and wild card in the Republican presidential race.
Mitt Romney, a Mormon, is losing the evangelical vote, but winning among Catholics. Rick Santorum, a Catholic, is losing the Catholic vote, but winning with evangelicals.
Two months ago, more than 150 evangelical leaders gathered at a Texas ranch and declared their support for Santorum. At the time it attracted little attention.
Few gave the former Pennsylvania senator's candidacy much of a prayer. Romney seemed to have a lock on the nomination.
But pundits underestimated the depth of evangelical discontent with the former Massachusetts governor, which has deepened since his failed 2008 presidential bid.
"Evangelicals make up a large portion of Republican primary voters," said John Green, a political scientist at the University of Akron who specializes in religion and politics. "In Ohio, it's more than 40 percent. In southern states, it's much larger. This is hurting Romney."
Roughly a quarter of U.S. adults identify themselves as evangelical Christian. Their dissatisfaction with Romney stems from his religious views and his flip-flopping on abortion and family issues dear to them.
Santorum strums those social-issue heartstrings. He won solidly in this week's Alabama and Mississippi primaries, where eight in 10 voters identified themselves as evangelical.
"The more religiously devout a voter, the more likely they will not vote for Romney," Green said. "Religious voters prefer Santorum."
If Romney becomes the party's November counterpunch to President Obama, his troubles with evangelical voters won't end. Their failure to turn out at the polls in swing states such as Florida, North Carolina and Ohio could thwart his bid to become the nation's first Mormon president.
"Given what's happened in the primaries, the question on everyone's mind is if Romney is the party's choice, will white evangelicals turn out to vote in the fall?" Green said. He distinguishes evangelicals by race because nonwhite evangelicals lean Democratic.
In a telling moment, the Rev. Robert Jeffress, a nationally prominent Baptist pastor based in Dallas, declared his support for Santorum while denouncing Romney's religion as a cult. Even so, Jeffress told MSNBC he'd "hold his nose" and vote for Romney in November if he's the GOP nominee.
But he's worried that other evangelicals won't vote at all. Speaking on Fox News' "The O'Reilly Factor," Jeffress said:
"In the 2008 election, 30 million evangelical Christians sat at home and didn't vote because they weren't energized by John McCain. Barack Obama won by 10 million votes. And I do think you can win the Republican nomination without evangelical Christians; you cannot win the general election without them."
Heading into today's Missouri caucus, Romney leads the delegate count with 495 from victories in 18 states. Santorum is a distant second with 252 delegates from wins in nine states. The difference between Romney's support among evangelicals and nonevangelicals is a staggering 19 percentage points, according to polls.
Santorum is capturing evangelical voters because he's more akin to them on social issues, according to the Rev. Thomas Reese, coordinator of the religion and public policy program at the Woodstock Theological Center at Georgetown University.
"Catholic Republicans tend to be more moderate than Santorum and evangelical Republicans, which is why they're voting for Romney," Reese said.
In 1961, when John F. Kennedy, a Democrat, became the first Catholic president, evangelicals denounced him because of his faith. Today, doctrinal differences are less important between the groups.
In the 2008 presidential election, white Catholics were evenly divided between McCain and Obama. Hispanic Catholics, repelled by Republicans' harsh anti-immigrant rhetoric -- now used by Romney and Santorum -- turned out in droves for Obama.
"Catholic Republicans tend to be more concerned about bread-and-butter issues -- jobs and the economy," Reese said. "But Santorum has used religious-liberty issues to galvanize evangelical support."
In the end, that may not be enough to overtake Romney, but merely to protract a race that already seems to have lasted an eternity.
Susan Hogan is a Star Tribune editorial writer.
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