In a June 26, 2004 interview on Larry King Live:

KING: Do you ever think of running for office?

REAGAN: No…

KING: You’ve got a pretty good name going in.

REAGAN: It seems to work for some people.

KING: Wouldn’t hurt you.

REAGAN: No, I’m not really cut out to be a politician. You know that I sometimes don’t know when to shut up. That could be a drawback. I’m an atheist. So there you go right there. I can’t be elected to anything because polls all say that people won’t elect an atheist.

From celebatheists.com