First off, keep in mind that, once you get beyond the simple “voting record”, there often isn’t a clear-cut distinction 'tween the two major parties (a gray area, if you will).
Second off, some people may call themselves one thing, while their actual beliefs may fall into line with another.
Thirdly, I have no doubts that there have been just as many crazy, evil, stupid liberals as there have been crazy, evil, stupid conservatives. I believe the OP is aware of this, so this isn’t a debate about “Which party is more evil?”
Now, onto the bulk of the response…
The people who seem to be the most vocal anti-KKK (Jesse Jackson, NAACP, etc.) also seem to be a tad more liberal, so it’s very convenient for them to label the KKK as conservative/Republican (I am neither agreeing nor denying this assertion). I imagine that if someone tries to disagree with these assertions, they’re branded as pro-KKK, and thus, they choose to avoid voicing their dissent (feel free to disagree with that… it’s 2:19 AM, and I’m going to bed after this post).
However, it’s very easy to list Tim McVeigh and Ted Kazinsyxzzxkyskxkzksjhgaf- uh, the Unabomber (you try spelling his name off the top of your head when you’re sleep-deprived!) as “liberal”, since they seemed to be very anti-“establishment” (peace out, man!) along with being rather activist-esque about carrying out their political standings.
In either case, I think it’s clear that the more-extreme examples of humanity are just that… extreme. Ted Bundy is in no way the “average” American (but is he related to Al at all?). Anyway, off to bed with the SPOOFER!!!