Should Kerry ignore the South?
The '00 election is complicated a little by the Nader vote, but in 5 states (Arkansas, Florida, Louisiana, Tennessee and Virginia), the difference between Bush and Gore was 8% or less, ignoring the Nader votes altogether. Clinton carried 4 of the 5 - not VA - in '96 (but the Perot vote adds even more complications).
That means a 4% swing in the vote (say from 54-46 to 50-50) would have shifted those states (64 electoral votes, including FL's 25) to Gore. A 10% swing in the vote would have given Gore all of the South except TX (and TX if you give Gore the Nader votes).
I don't know how close the polling is between Bush and Kerry in the South. Also, Gore was arguably a Southern candidate - don't know how much difference that makes either, but Kerry beat Edwards in GA.
4% or maybe 10% should be achievable with a smart campaign. Even if you can't swing 4% (and some states - FL obviously - switch well below that), if you can threaten, you can force Bush to have to divert resources away from swing states to what he thought would be "safe" states, possibly making the swing states less "swingy" too. I would also expect that to force Bush to the right too, which also helps Kerry in other places.
From the Pew survey cited in an earlier story on dKos, 55% of the Independents were in the South; the South has a large black population. I don't know how much turnout could be improved, but if blacks are as bad as whites at voting, a lot.