Is there anywhere besides Mississippi where this might be a possibility? Louisiana maybe? California someday?
There are a lot of steps I feel to get to this outcome, but it is a logical one. First said state can't be just 50% AA, it has to be something around 60% so that a case for white suppression can be justified. Then you probably need a supreme court case that will accept the argument to extend the VRA in cases where one non-white group possesses a commanding majority.
In the case of the SW states, it also probably requires Hispanics to not be integrated into the collective american definition of 'White' by then, in a similar vein to how Irish, Italians, and Slavs were in the 20th century. The only demographic group that has avoided cultural integration historically are African Americans, so perhaps this case will only ever end up applying to various regions of the deep south.