Via Strange Maps we have some freaky stuff. Beow are two maps separated by 150ish years. The first is a county level snapshot of Obama's wins in a section of the South. Blue being Democrat, red being Republican.
The second, as the title says, represent cotton production density in the same area of the South in 1860, where, clearly, those who would have been picking cotton were segrated former slaves of African origin.
Now take a look at the overlay.
Now I'm not making any correlated conclusion, but the maps is interesting nonetheless. Lots more comment about it on the original post.