Over the years I have taken note of the political stickers on cars that have driven dangerously around me (bear in mind that I'm almost exclusively travelling by bicycle so dangerous motorists definitely get my attention). Almost without fail, the rudest most dangerous motorists have stickers for the most left-wing candidates. As someone whose politics are to the left of Bernie, this really galls me, but it is what I observe.

As far as good drivers being the exception, I'd say they are almost unicorns. Also, the folks on bikes ride like they drive, which isn't very inspiring.