From the Sox? Ellsbury has the best chance. He's got the potential to be a 30 HR, 30+ SB, .300+ hitter, 100+ Runs, 100+ RBI guy this season, which is unbelievable. An absolute complete player, and he plays top notch defense in center field. I know a lot of people are going to argue that Granderson has had the better year, but his defense has been really bad, and this isn't the Silver Slugger, it's the MVP. Defense actually counts here. Now, whether the voters actually look at that or not, who knows, but if you ask me, Ells has the best shot.
Also, Adrian's power outage has hurt him pretty bad. One homerun in his last 157 PA is brutal, and he's got 2 RBI in August.