I don't see Chad having a career year, so I voted for that.
In truth though, Ridley getting the ROTY is so astronomically unlikely that that would be the real winner. It's just not the really plausible enough to vote on. It would be near impossible for a RB to win ROTY in our system.
Now if you may it something more realistic like Ridley will have the most yards/tds/etc... of all the RB's on the team, then I would have voted there. That's unlikely to happen, but it's a realistic possibility.