Once you realize how low, unethical and character-destroying these people are, how can anybody support them with a straight face?
Unfortunately, my brother is a big lib and in his case he simply ignores or dismiss anything bad that's associated with his side. It's simply stunning at times to hear him talk. The evidence of against the democrats that he supports can be as huge as the Statue of Liberty but he won't acknowledge it. He still believes in Dan Rather's story about Bush.
I think the real issue with my brother is that he's a narcissist. Most liberals are.