Definately the Pats. Not too many people could name anyone on their offense going into the year. Brady wasn't even the starter at the beginning, and he hurt his ankle in the AFC Championship game. I remember wanting Bledsoe to start the Super Bowl.
The Rams were favored by like 17 or something ridiculous. The introductions were amazing though. The Rams have their unstoppable offense announced individually while the Pats come out as a group. I'm getting off topic. I do think that people should give the Cards more of a chance though. We've seen time and time again that when teams are "supposed" to have no trouble with another team, it doesn't always work out.
Not only the Rams and Pats, but going in to the Rose Bowl last year not many gave Texas a shot.
I find it interesting that most Cards fans were probably on the other side of this for that Super Bowl, while I'm on the underdog side both times.