Personally. I always felt that a very large portion of Confederate generals would move into the political circle after the war.
The exceptions of course would be Forrest and Lee. Lee because of his age, and generally how apolitical he was. And Forrest, largely because he kept his political ambitions confined to Memphis and Mississippi and he was more concerned about business and money.
I am not saying that's who I would be a big supporter of, but I'd bet he'd be on the ballot, and would win. My personal preference would also be other. Louis T. Wigfall. But I doubt he would been on the ballot period.
Haha, I almost said Wigfall too, but other than having a cool name, I agree he would not have made a serious candidate, too polarizing. I agree, Stephens would have most likely been the second President.