A lot of those are more party changes than ideological... Places with major demographic shifts like dekalb county GA would certainly qualify. If we're looking for a more ideological shift, northern Idaho is a good candidate. It used to be much more economically left wing.
Yep, the loggers and miners either died or left the state and they were replaced with John Birch Society members from the OC. We still received a decent contingent of latte liberals who have made the core of Sandpoint and Coeur d' Alene more prone to voting straight D.