Seems to turn off Northeast and West Coast voters.
What's worse, some regions of the South such as Northern Virginia and South Florida don't even share a southern culture anymore.
The focus has been on gay marriage lately and how it's wrecking the GOP with moderate voters, but maybe the bigger issue is the overall culture Republicans are perceived to have.
Same-sex marriage is dying as a political football. It's as much a political football with Michigan Republicans as it is with Texas Republicans. Republicans will have to move to economic issues and a chest-pumping foreign policy.
Northern Virginia and South Florida (and to only a slightly-lesser extent much of North Carolina) are increasingly being 'settled' by Yankees who take their political culture with them. PPP often shows this in some questions that ask about loyalties to sports teams -- and those loyalties are extremely strong. If you were a fan of the Detroit Tigers as a child, you are probably still a fan of the Motor City Kitties. So if the people around Austin, Texas include lots of Giants, Dodgers, Cubs, Tigers, Indians, Yankees, Red Sox, and Phillies baseball fans, then the local politics are more likely to look like those of Des Moines than those of small towns maybe fifty miles away (where people are more likely to be Rangers or Astros fans).