From the campaign website of Senator David Vitter (R-La):

Vitter Statement on Protecting the Sanctity of Marriage

“This is a real outrage.  The Hollywood left is redefining the most basic institution in human history, and our two U.S. Senators won’t do anything about it.

We need a U.S. Senator who will stand up for Louisiana values, not Massachusetts’s values.  I am the only Senate Candidate to coauthor the Federal Marriage Amendment; the only one fighting for its passage.  I am the only candidate proposing changes to the senate rules to stop liberal obstructionists from preventing an up or down vote on issues like this, judges, energy, and on and on.” stated David Vitter.

This is how he was described in a 2004 profile in Salon:

A family-values far-right conservative named David Vitter appears headed for victory on Tuesday in the U.S. Senate race in Louisiana. . . . He presents himself as a morally righteous, clean-cut family man, and his wife and three young children have become virtual campaign props. . . .

Sounds like a stand-up "family values" kind of guy, huh?  Except — whoops, there it is:

Louisiana Sen. David Vitter, whose telephone number was disclosed by the so-called "D.C. Madam" accused of running a prostitution ring, says he is sorry for a "serious sin" and that he has already made peace with his wife.

He may have made peace with his wife, but if he’s smart, he’ll sleep on the couch for a while.  Because this is how Mrs. Vitter was talking in an interview in 2000:

Asked by an interviewer in 2000 whether she could forgive her husband if she learned he’d had an extramarital affair, as Hillary Clinton and Bob Livingston’s wife had done, Wendy Vitter told the Times-Picayune: "I’m a lot more like Lorena Bobbitt than Hillary. If he does something like that, I’m walking away with one thing, and it’s not alimony, trust me."

UPDATE:  Vitter got his start in Congress after replacing former Rep. Bob Livingston (R-LA), who “abruptly resigned after disclosures of numerous affairs” in 1998. At the time, Vitter argued that an extramarital affair was grounds for resignation:

“I think Livingston’s stepping down makes a very powerful argument that Clinton should resign as well and move beyond this mess,” he said. [Atlanta Journal and Constitution, 12/20/98]