Former Republican presidential candidate Rudy Giuliani thinks his party is making a serious mistake by mounting a national effort to oppose marriage equality.

"I think that marriage should be between a man and woman, but I think that the Republican Party would be well advised to get the heck out of people's bedrooms and let these things get decided by states," Giuliani told CNN's Candy Crowley Sunday.

"You can live with it, it's fine?" Crowley asked. "You don't see any harm that's going to come to New York [from legalizing same sex marriage]?"

"I don't see harm. Although, I think it would be better for stability of families if we kept marriage between a man and woman. I see more harm, however, by dwelling so much on the subject of gays and lesbians and whether it's right or wrong in politics. We've got far -- not necessarily more important things -- but far more relevant things to talk about," Giuliani said.

"I think if you are a libertarian Republican or you have a streak of libertarian Republican, I don't know what the heck the Republican Party wants to do getting involved in people's sexual lives and personal lives so much for. Stay out of it and it would be much more a successful party if we stuck to our economic, conservative roots and our idea of a strong, assertive America that is not embarrassed to be the leader of the world."