I'm going with Alpha from Godolphin Racing because Alpha is the first horse Godolphin has trained in America on American tracks. Their previous eight entries were all trained in the UAE before being shipped to the United States. The Dubai crowd are hot to win the Kentucky Derby. I think Alpha's training regimen will serve him up a victory of roses.
But I wouldn't completely dismiss Union Rags, Bodemeister, or undefeated Gemologist. All of them could be in the race, as well as Take Charge Indy with Calvin Borel in the saddle. Borel has won three Derbys since 2007.
Check out my Hub, "Part One Kentucky Derby Thoughts and Tips From the Thoroughbred Contenders".