A few thoughts:
The incoming (black) mayor won over 50% of the vote in a three way race. In a town that is 70% white. Conversely the outgoing mayor was beat by long serving employee her husband fired.
Presumably, the voters in this fairly small town knew both these women. My take that they had had enough of this classless b-—h and her reaction to the loss reinforced the point.
There is nothing like small town drama.
Sounds as good a theory as any.