I listen to WAMU at work online, and the Diane Rehm show plays there since she's based out of DC.
They had a Clinton supporter call in, saying she could never vote for Obama because it should have been a woman on the ticket. When asked if she was voting for McCain, she said this:
"Oh no. I've voted Democrat all my life. And I know he was in a box for eight years [sic] and I'm really sorry that happened to him, but I wouldn't want someone like that with his finger on the button. I think he's a little warped, to be honest."
She went on to say she's probably going to write in Clinton in protest, or maybe vote for Cynthia McKinney instead.
Those 18 million cracks are, for the most part, smart enough not to vote for McCain.