“I don’t think I’m even going to bother asking him that, because it’s a very sensitive subject for his wife and him,” said Chris Terrell, a spokesman for Livingston’s lobbying group, when asked whether Livingston would answer questions on how his marriage has held up.

The list of ongoing political marriages runs long. “I have a file folder that I set up probably 20 years ago, and I labeled it ‘affairs in high places,’ ” said Emily Brown, a social worker who has counseled Washington couples with marriage problems.

“It’s packed full, and it’s been a gradual filling. But there’s always something going on.”

So what’s their secret? How do these marriages make it?  

Susan Semeleer, a former Republican crisis communications consultant, explained that people who enter politics are of a different ilk. Political couples generally don’t deal with marital strife in the same way everyday couples might.

“It’s instructive that the wives don’t leave, and it does make one wonder about the deals that get struck between public figures and their spouses,” she said.

Nonetheless, it takes a lot of work to salvage a marriage after it’s been hit by scandal, Brown said. The couple has “to do the emotional work, and for them to continue the marriage, they both need to do it,” she said.

Brown said she doubts that the Craigs have fully worked through the issues their marriage faced last year.

“His wife has got to be hurting,” she said. “He’s probably scared and hurting, but is it OK for a congressman to see a therapist? I think people who are so visible become so embarrassed that it gets in the way of them seeking help.”

Both Brown and Semeleer pointed to the Clintons’ relationship as the most notable disaster in political marriages. Brown predicted that if Sen. Hillary Rodham Clinton (D-N.Y.) doesn’t win the presidential election, the couple will split.

But sometimes a political bond is stronger than love.

“Wendy Vitter — if her husband was David Vitter the bus driver, she probably would have left him,” Semeleer said. “But when your humiliation is unfolding on CNN, it’s a little harder to walk away. It’s an admission of defeat.”