For me it'd be Stafford. Since I'm in the Detroit area I've heard a lot of flak about Stafford and its nice to see him prove his Detroit, and other critics, wrong. I'd love it for him to win another SB just to really shut them up for good.
I root for Kupp because he was a total nobody but became a star through hard work and discipline. It's nice to see the little guys make it big.
I root for Allen because he proved me wrong. Prior to last season I didn't think 2 cents for him and I wanted him replaced. When I heard he was going to be the starter I was bummed and disappointed. But he worked real hard during the offseason and turned into a top rated center. I hope he repeats the same offseason work effort and becomes a real terror as a center next season.
