Right you are. State population is about 35% black. Those counties which went for the "1" are overwhelmingly black, e.g., the "black belt" counties which were designated such for the color of the soil and then later because so many slave holders settled in the same area.
Of course, bankrupt Jefferson County has Birmingham, which is 72% black. 'nuff said.
Alabama is 26.5% black, 66.8% white, and then other, per US Census stats.