I didn'thave a party or regional dig in mind when I started this thread , it certainly turned into one fast enough.
The KKK is a race themed organisation , it accepts the wealthy and the poor , the well educated and the poorly educated the northerner and the southerner.
The waning of Racism is the biggest reason for the waning of the KKK , it would not disappear if the South were evacuated or if we all became wealthy university graduates.
Government and non government watchdogs appropriately watch to keep them from getting away with crimes , and public disgust and ridicule reduces their appeal for even the stupid.
Pointing at a class or a region as being the natural home of the opprobrious organisation is dodging the truth , racism is home anywhere it finds welcome and that can be literally anywhere.