That’s the old cotton belt. A blue belt hidden within a red zone.
But geography’s effect on elections extends back even further into the past. In 2008, Obama lost a swathe of southern states to Republican contender John McCain, but if you drill down to county level, a remarkable blue streak cuts through Mississippi, Alabama, Georgia, South Carolina, and Virginia. This pattern makes no apparent sense, unless you link it to an agricultural map from the 1860s — showing where cotton was king. Those areas are still heavily populated by the descendants of the slaves once forced to work the cotton fields; the African-American voting bloc behind Obama that helped him win 2008 — if not in the aforementioned southern states. The reason cotton grew best where it did goes back about 100 million years to the Cretaceous Era. Back then, the cotton belt was a coastal area, and the graveyard of untold billions of single-celled creatures called plankton. Their dead bodies would become the chalk deposits upon which cotton would thrive.
The View from the Bell Tower 