The Republican field was pretty lackluster in real life and I doubt it'll be any better in a world where no economic crisis is weighting down Obama. Without the economy as an issue to run on, the Republicans would only be able to campaign on opposition to Obama's polices, which, while rallying the base, would probably not rally many moderates and independents to their cause. I could see Obama winning very decisively by an even larger margin than he won real life '08.
On the issue of Georgia, the margin between Obama and Romney in that state was closer than either Missouri or Arizona in real life '12, so I wouldn't completely discount the possibility of it going to Obama in this scenario. It would be a tough fight, but not impossible.
