Broncos, Cards, Panthers, Patriots
I despise the last two, but even they're separated by gulf of detest. Like others have said, Broncos winning would enrage Pats fans. Plus, they kinda deserve a high after that low of SB48. Don't like Arizona much. But compared to the other NFC team? I watched that NFL Network special on Arians and don't hate him as much. And again, after their SB against the Steelers and last season's demise, on top of their entire history, they're due a title. Like many others, I loathe Cam. He's like the John Cena of football. Seems like a great guy off the field, even in commercials. And some of his fans use him like an avatar. Insufferable. Needn't say anything re: Pats...
Edit: What's the toughest SB you watched, because of the teams (excluding Seattle)? I've only been watching since Nov. 2007. I actually rooted for the Pats against the Giants.