Lupin is my favorite character, but since he wasn't placed in the poll, I voted for Snape.
I like Snape a lot because there's so many facets to his character, he's mean to Harry and friends, but he fights for the right causes on the right side. It sounds like he had a lousy childhood before he went to Hgowarts, and once there, was picked on terribly by the two blokes! Not that he's to be held blameless, but, I don't know, he's just totally cool!