If Dallas takes a RB in the first round, whomever it is, they will likely have the most fantasy football impact. I doubt Hambrick could keep his job unless his competition were walk-ons, and Parcells loves to pound the ball for clock management. So, no matter how good the guy is, if he's durable, he'll get a lot of carries.
If Denver grabs a 1st round RB, they'd have to be next in line. Portis, Anderson, Gary, Davis. Gotta give history some credit here.
The long shot (because you never know how Bellicheck will use him) is the RB New England will likely take.
I suppose if Detroit takes a RB they go in contention as well, but aside from that I wouldnt not expect another rookie running back to see more than 2 games worth of action.