Yeah, but those people are Republicans, they aren't going to all of a sudden vote for Obama. The only place he can improve is among white independents.
Southern poor whites will vote for Mike Huckabee in a large percentage if he gets the nomination of the Republican Party. Other than that, they aren't at all reliable GOP voters in 2012.
Since 1968, the southeastern US has been the most capricious in its voting. It is the only region in which any third-Party candidates have gotten any electoral votes. It voted for Carter in 1976 when the rest of America voted for Ford; it split about 50-50 for Clinton in 1992 and 1996. Three former-Confederate states voted for him in 2008.
The Republican identity of Southern voters isn't so dyed-in-the-wool as it might seem. Arkansas has two Democratic Senators.