Update:

Commenter Sam points out that Edwards will poll lower in Tennessee than his native South Carolina. So, when I recalculate capping Edwards at 15% and splitting the remaining white vote 2-to-1 for Clinton I come up with this:

Obama: 45%
Clinton: 39%
Edwards: 15%

Closer, but the math still looks difficult for Clinton if Obama can maintain his huge 4-to-1 advantage with black voters. As I said, Obama is likely to do better among Tennessee's whites than in the more racially polarized South Carolina. Also, interesting to note is that Harold Ford Jr. pulled 48% among all Tennesseeans in 2006.

(Original post here)

Super Tuesday is coming and Barack Obama's ability to capture the lion's share of black voters could tilt several states into his column. South Carolina is 29% black and they made up 55% of the voters in the primary there. Here is the percentage of the black population in some key Super Tuesday states:

Alabama: 29.2%
Arkansas: 15.5%
Delaware: 20%
Georgia: 27.5%
Illinois: 15%
Missouri: 11%
New Jersey: 15.3%
New York: 15.7%
Tennessee: 16.1%

Now consider some of the South Carolina exit polling data:

Black voters dominated the South Carolina primary and voted overwhelmingly for Barack Obama, with 78 percent supporting him. Nineteen percent of blacks voted for Hillary Rodham Clinton. While a quarter of whites voted for Obama, three-quarters of whites split their votes between the two white candidates, Clinton and John Edwards, voting 40 percent for Edwards and 36 percent for Clinton. Edwards' support came almost entirely from white voters.

If these patterns are repeated on Super Tuesday then Obama should cruise to victory in Georgia and Alabama by a wide margin. States like Tennessee get more interesting. Assuming that blacks make up 30% of the turnout and that we see the same breakdown along racial lines as in South Carolina the result would be:

Obama: 40%
Clinton: 30%
Edwards: 29%

In actuality, Obama is likely to do better than the 25% share of white votes he received in South Carolina because Tennessee is not polarized as much. Obama has proven in Iowa and in New Hampshire (where he came in second by just 2%) the he can pull white votes.

In addition to Georgia, Alabama and Tennessee Obama should handily win his home state of Illinois. Clinton's advantage in New York, New Jersey, and Arkansas is probably unassailable. Missouri, Oklahoma and, most importantly, California could be real dog fights. Obama doesn't need to win all the battleground races however, he just needs to scoop up a fair share of the delegates that are up for grabs.

The bottom line is that Super Tuesday won't be the end of this campaign on the Democratic side. Obama should have several wins that day to keep his campaign going. Keep your eyes on the big prize: California.