I'm not sure why everyone thinks that blacks only trended democrat because of Obama...
Is everyone forgetting that Republicans did everything they could to suppress the minority vote in the last election? How could any black voter want to vote for a party that literally doesn't even want them to vote in the first place?
I guess I could see some who are super rich voting Republican in hopes of lower taxes, but that's about it.
Well, if you check virtually every Senate Race 2010-2012 in a southern state the democrat almost always gets <90% where Obama got >90% both times. Not only that but in the presidential elections Obama had better turnout among blacks, but the democrat in those same states in the Senatorial race get less % and turnout.
Take the Mississippi Senatorial Election for example:
White (60%) = 87% Wicker, 11% Gore
Black (35%) = 88% Gore, 10% Wicker
Compare that the the presidential election:
White (59%) = 89% Romney, 10% Obama
Black (36%) = 96% Obama, 4% Romney
Turnout difference wasn't significant, but the % of the vote won was. Basically all the the states you check for exit polls in Senate Races blacks vote between 80-90% democrat, but Obama got >90% easily in both elections. Except in cases of Illinois and New York, you don't find many times where blacks go >90% for the democrat. Turnout was also much lower in the Bush elections (and in mid-terms) than in the Obama elections. Just something I would like to point out.
We'll have to evaluate if this is a real trend for Obama in 2016, but right now its still a plausible theme.