Orville Hubbard is a good candidate but white supremacy was not merely a Southern phenomenon. Indiana was nicknamed the KKK capitol in the 1920's, there was a sundown town in Connecticut and at least one politician in Maine had KKK/white supremacist ties. Surprisingly the now-progressive cities of Denver and Portland Oregon had its own connections as well as mayors in both cities had KKK ties, I believe the mayor 100 years ago of the later was friends with The Grand Wizard.
