Also, as David Limbaugh's better-known younger brother once pointed out, liberalism is an attitude, conservatism is a way of life. It's the easiest thing in the world to be a liberal: all you have to do is say the right things and purport to hold the right attitudes. Now, you don't actually have to walk the walk, if it sufficient to simply talk the talk. You don't even have to believe what you say, just pretend to.
In liberal eyes, a genuinely bad person with the right attitudes (Bill Clinton comes to mind) is a superior person to an ethical person with the "wrong" attitudes.