Too Late to Change my Vote?

Barack Obama is a likable guy. Despite his obvious leadership skills, I'm sure the likability factor was high on the list of reasons why he won the presidential election. That's also why I'd like to change my vote. Every time I turn on the news, I see another reason to spare Obama. I'm starting to feel bad that my vote is sending this nice dude and his cute little fist-bumping family, complete with a new puppy, into the line of fire. Why do I get the feeling that John McCain is somewhere snickering right now?