On that poll, I'd be willing to bet that the group that hates the Cowboys is mostly made up of Eagles fans. I lived in Philly for a while recently and had to convince people that I was not a Cowboys fan as soon as they found out I was from Dallas. Those people back their NFL team more than any other city, easy. The closest thing to it I've seen was the way San Antonio backs the Spurs.
I'm actually a Colts fan. I would pay alot more attention to pro sports if they were played by more guys as respectable as Peyton Manning. I think they will really take off as soon as they can figure out how to beat the Pats.