Some brief quotes from U.S. Senator John Ensign (R-NV), GOP leader of the Republican Policy Committee and a man hinting at a 2012 presidential bid, on the subject of marriage:

1998: While running for Nevada’s Senate seat against Harry Reid, Ensign called on President Clinton to resign in light of his admitted affair with former White House intern Monica Lewinsky:

“I came to that conclusion recently, and frankly it’s because of what he put his whole Cabinet through and what he has put the country through,” Ensign said Thursday, becoming the first member of the Nevada delegation to call for Clinton to quit. “He has no credibility left.”

Feb. 2004:  Ensign announces his support for an amendment to the Constitution that would have defined marriage as a union between a man and a woman. Ensign said the amendment, which ultimately failed, was necessary to protect “the institution of marriage“:

“Sadly, the effort to redefine marriage against the wishes of a majority of the people is, with help from activist judges, succeeding,” Ensign said. “In order to defend the institution of marriage, uphold the rights of individual states, and maintain the will of the people, I believe we are compelled to amend our country’s constitution.”

“The effort to pass a constitutional amendment reaffirming marriage as being between a man and a woman only is being undertaken strictly as a defense of marriage against the attempt to redefine it and, in the process, weaken it,” Ensign said. “Marriage is an extremely important institution in this country and protecting it is, in my mind, worth the extraordinary step of amending our constitution.”

October 18, 2007: "There's too many people that paint with a broad brush that we're all corrupt, we're all amoral. … And having these kinds of things happen, whether it's a Republican or Democratic senator — we certainly have had plenty of Democratic scandals in the past — we need people who are in office who will hold themselves to a little higher standard." – John Ensign (R-NV)

April 19, 2009: “I believe that marriage should be defined as that between one man and one woman. You want to do what is ideal for children and all of the studies show that the ideal for children is to be in a household with a father and a mother.” – John Ensign (R-NV)

TODAY (the predictable punchline): "I came home to Nevada to come forward and explain to the citizens of our state something that I was involved in about a year ago. Last year I had an affair. I violated the vows of my marriage. It is the worst thing I have ever done in my life. If there was ever anything in my life that I could take back, this would be it…. I take full responsibility for my actions." – John Ensign (R-NV)

UPDATE:   Oh, and Ensign is a longtime member of the Promise Keepers, a conservative evangelical group that promotes strong families and marriages.