I'm not really sure I understand American party politics:
Holocaust denier and former leader of the American Nazi Party will almost certainly be Republican candidate for an Illinois congress seat.
The reason I say that I don't understand US party politics, is that this guy is heinous enough that even the GOP doesn't want him, and have actively blocked him from running in the past. But this time, somehow, for some reason, they can't prevent him.
So can anybody who fancies it just declare themselves part of a political party and the political party themselves have no choice in the matter? Why don't Republicans just take over the Democratic party, then? Or vice versa.
I feel like I must be missing something, because that's just really weird.