Publishers weekly review of the Sundown Towns book:
An online database of suspected Sundown towns:
http://www.uvm.edu/~jloewen/content.php?file=sundowntowns-whitemap.htmlWith a pretty large number of former and possibly current towns in Missouri, Indiana, and Illinois. The book mentions more from Illinois, the database includes 97 entries from Missouri.
The book also mentions how the majority of those towns were in the North.
So if there's some coherant electoral trends to these areas, then that would be interesting.