I hear many people on forums (and elsewhere) say they won't bother to vote. For some, it appears to be a range from general apathy to downright despair. For others, it appears to be someone kinds of psychological defense mechanism that bolsters self-image. That person wants to be above it all. He does not vote because then he can hold on to some type of illusory integrity.
You are either political by commission or omission. I understand general malaise, but there are people who are committed. They are people sitting on their couches getting a ride to the polls. They just have someone telling them who to vote for. The non-voter also sits on the couch, but defiantly holds up his illusory integrity.