While Mark Sanford works to salvage his marriage, Republicans are facing the prospect of a different kind of breakup: religious voters walking out on the GOP.
A series of sex-related scandals over the last few years has undercut the party's assertions of moral authority and, worse, may serve to reinforce the doubts that many evangelical voters have traditionally harbored about the unholiness of the political realm.
"If we place our hope in a political party or a politician, we'll be let down," said Brandt Waggoner, 25, a student at Southeastern Baptist Theological Seminary in Wake Forest, N.C., who said he spoke for many young evangelicals. "My hope is in God and not in the government."
A sudden and overwhelming shift of Christian conservatives from the GOP to the more secular-minded Democratic Party appears unlikely. As Laura Olson, an expert on religion and politics at South Carolina's Clemson University, put it: "The Republican Party is still going to be, at a minimum, the lesser of two evils."
But in politics, subtraction can be just as important as addition. If large numbers of evangelicals were to stay home on election day, or channel their activism into outlets other than politics, the GOP could suffer grave consequences; over the last generation, devout churchgoer voters have become an increasingly vital part of the shrinking Republican base.
There are, of course, plenty of Democrats who have, like South Carolina Gov. Sanford, broken their marital vows and lied to the public about their actions.
"The fact is, within any group you're going to have some people who make mistakes," said David Winston, a GOP pollster in Washington, who cautioned against painting Democrats or Republicans with too broad a brush. "It's not systemic to any one party."
In general, however, Republicans have been far more active in reaching out to religious voters, not just through conservative positions on abortion, school prayer, and lately same-sex marriage, but also by promoting an image of greater virtue and more godliness.
That makes it all the more damaging when prominent figures in the party -- especially those espousing Christian values, like Sanford and Sen. John Ensign of Nevada -- are caught transgressing.
Their back-to-back confessions of marital infidelity place the two men in a lineup that includes, in just the last few years, former Sen. Larry E. Craig of Idaho, who pleaded guilty to disorderly conduct in an incident in a men's bathroom at the Minneapolis airport; Sen. David Vitter of Louisiana, who was identified as the client of a Washington prostitution ring; and former Rep. Mark Foley of Florida, who resigned after sending sexually explicit e-mail messages to male congressional pages.
"Episode after episode like this makes it relatively difficult for Republicans to say with a straight face that they're a party that stands on moral issues that evangelicals care about," said Dale Kuehne, an associate political science professor at Saint Anselm College and a pastor in Nashua, N.H. "You look at Mark Sanford and Larry Craig and say, 'Is there anyone we can trust?' "
Margaret Feinberg, for one, has grown increasingly skeptical of all politicians. The thirtysomething evangelical author from Colorado doesn't differentiate between parties; she's turned off by all of the seamy revelations of low-life behavior in high-flown places.
"The . . . rumors and sexual details make me want to avoid the voting booth altogether," Feinberg said. "My head says that every vote counts, but my heart aches at the impropriety. How can I trust someone to uphold the laws of the land when they can't uphold their marriage vows?"
Historically, evangelicals have cycled through periods of political engagement and withdrawal from the electoral scrum. The latest activism began in the 1970s, when liberalism had evidently run its course and religious leaders like the late Rev. Jerry Falwell galvanized Christian voters and turned them into a force for conservative values and political change.
"We may be coming to an end of [that] cycle," said Corwin E. Smidt, a pollster and political scientist at Calvin College, a Christian liberal arts school in Grand Rapids, Mich. If nothing else, Smidt said, scandals like the Sanford affair make religious voters "more likely to second-guess themselves . . . and certainly increase disillusionment."
At the very least, some Republicans say, the party's politicians need to lower their voices and show some humility when addressing issues of morality and personal responsibility.
"We really do need to cut loose this stinkpot of self-righteousness," said Bob Inglis, a GOP congressman from South Carolina who once served alongside Sanford on Capitol Hill. "I see a real opportunity for a more accurate presentation of the Gospel in presenting fact rather than the fiction . . . that we're paragons of virtue."
Times staff writer Duke Helfand contributed to this report.