This is just an anecdote, so make of it what you will.
Today I hosted Mike Jacobs, a Republican state legislator who recently left the Democratic Party. I’ve always found him (even in his previous political life) to be a thoughtful and animated public servant, trying faithfully to serve his district, which, Wikipedia to the contrary notwithstanding, probably leans a little Republican, albeit (like the districts surrounding it) more on fiscal and economic than on social grounds.
Jacobs’s public explanation of his party switch is interesting: as he thought about the ballot he cast on Election Day in 2006, he found himself voting more for Republican candidates statewide than Democrats. (When he last spoke at Oglethorpe as a Democrat, he remarked that he thought that the Party had a long way to go to become competitive again statewide.)
As he negotiated his party switch, he made it clear to the Republican legislative leadership that he couldn’t and wouldn’t conform his views on social issues to those of the majority of the caucus. Fair enough; I don’t agree with him, but I don’t live in his district and, if I did, my voting options wouldn’t be extensive. (He says that the Democrats are going to run someone to his left, ceding him the center and the right.)
He also noted that he’s found more tolerance of his social issue heterodoxy in the legislative Republican caucus than he found of his fiscal and economic heterodoxy among his former Democratic colleagues. If one wished to snark at Republicans, I suppose one could say that that goes to show that they, in their heart of hearts, don’t really care about the social issues, but I’d prefer to think of them as grown-ups, recognizing that political effectiveness requires all sorts of imperfect alliances.
On the other side of the aisle, I think it’s fair to say that the Georgia Democratic Party, with perhaps a couple of noteworthy exceptions (the former more so than the latter), has pretty much become a mirror image of its national counterpart. It won’t in the foreseeable future spawn many genuine blue dogs, especially to the extent that they have to be cultivated in the state legislature.