Obama may get a slightly lower share (~92%) among them in 2012, but could get a higher share of Whites, especially in the Upper South (MO, IN, KY, OH, WV, VA, NC and maybe Florida or even the Deep South) if the economy is growing fast by Mid-2012 and Obama had a good term overall. Let's say he wins the General Election with a 10-point margin, I could see 45% of Whites voting for him.
Here's each Southern state, with the same turnout, but 45% of the white vote instead of the '08 %:
Alabama: 60.07%
Arkansas: 50.55%
Florida: 52.41%
Georgia: 60.45%
Kentucky: 49.8
Louisiana: 58.91%
Mississippi: 62.64%
Missouri: 50.19%
North Carolina: 56.05%
South Carolina: 57.75%
Tennessee: 50.28%
Texas: 53.69%
Virginia: 53.15%
Giving us this 2008 map: