Maybe Southerners have long memories of a bad history.
We are daily told [by the Mormons]
that we, (the Gentiles,) of this county are to cut off, and our lands appropriated by them for inheritance. Whether this is to be accomplished by the hand of the destroying angel, the judgments of God, or the arm of power, they are not fully agreed among themselves.
- Western Monitor (Fayette, Missouri), August 2, 1833; quoted in Brodie, No Man Knows My History, 1945, p. 131
If gentiles (Missourian Old Settlers) did not wish to live among the Mormons, they would be forced to sell out to them and most likely at a loss
. On the other hand, if the gentiles attempted to remain in Jackson County, Mormon immigration ensured the Saints would soon make up the majority of the population, which would thereby permit them to oust the old settlers through ostensibly legal methods.
- Kenneth Winn, Exiles in a Land of Liberty, p. 93
I understand that the South has a long memory, and I understand why, but that can't explain this remarkable division, unless you wish to assert that the South's somewhat "adopted" brethren westward to Kansas and through Texas retain that same memory, with the same level of animosity.
Equally, I recognize that Huck's wins went right across the traditional Bible belt, so one could infer that the evangelical protestants were lifting him up (undoubtedly the case). Romney was relegated to 3rd place, behind McCain throughout the region. But the Mountain West is less "evangelical" by a matter of mere degrees, yet Romney won the West, and Huck was behind McCain there.
It is just such an odd and symmetric difference in a set of regions that largely and often speak with a united voice.