I keep hearing how Romney won’t perform well in the southern states. Does anyone really believe that Obama will win the South over Romney?
Most of it, no.
However, we can't forget the power of black turnout in the South. Blacks traditionally have a horrible turnout percentage. Obama’s 2008 win happened in significant measure because of people who don't usually vote choosing to vote.
The end result is that North Carolina and Virginia are in play with a Romney nomination in ways that would not be with a Gingrich or Santorum nomination. Florida has long since ceased to be Southern in its core demographics except in the panhandle and other northern counties, and if Hispanics don't have a good reason to vote for a Republican, many are likely to vote Democrat. In a worst-case scenario with a highly motivated black turnout and a demotivated Republican base, several other states which usually vote Republican could flip Democrat as well.
I oppose Romney primarily because of ideological reasons — abortion is a core issue for me. However, pragmatic reasons would apply even if I were not dead-set against Romney's flip-flops on abortion, gay marriage, and other key Christian conservative issues.