Gregg is very smart, fiscal cautious and flinty. My kind of guy. Keating is scandal tarred (I don't remember the details, but they can be looked up).
Well, I didn't see any scandals tarring him on Wikipedia. Are you sure you're not thinking of the Keating Five (that's Charles Keating)? And the others? I could understand Rell not contributing a lot.
You can read more about Frank Keating
here. The scandal was a weird one involving a phony drug, money fed to Keating over a decade, and the founder of the Dreyfus Mutual Funds, Jack Dreyfus. It ended his political career, permanently. Prior to that he generated buzz.
I have become cynical about politicians for a reason. I have lived just too damn long. The Native Americans (some of them) had it right. At a certain point, dyspeptic geezers need to go up to the mountain to freeze to death. They just get to be too high maintenance and demoralizing, to the idealistic young filled with hope.