Leave it to a brain circulation cut off by Spandex to think she makes a point by quoting a novel.
Still, this particular fiction's scene does cite a genuinely historical entity. "Night riders", also called "Regulators" or "Slave patrols" were operating since at least the eighteenth century, before there was a country and way before there were any political parties. That's a major part of the element that took over the Klan from its original founders. Again, no political party was required to participate in either.
These "night riders", considered a civic duty of the (white) menfolk, operated primarily to hunt down and return runaway slaves -- and when there weren't any to hunt in that area, to ride around intimidating existing slaves as a way of discouraging runaways and insurrections. So while the Klan brought in costumes and a framework of secret rituals, its activities concerning ex-slaves were already long-established practice.
Slave escapes and insurrections quite naturally had been going on since literally the first African slaves were brought to these shores in the 1530s by a Spanish crew. That group of captives escaped and happily were never caught, presumably joining with, and surviving with the aid of, local Native Americans. Other revolts and escapes occurred, naturally, throughout the infamous history of slavery. The "night riders" were the white establishment's remedy for such escapes; a civil 'security' force. And they had nothing to do with politics.