I also live in a city where ballot access wars are just part of the political game. The signature requirements for local races really aren't all that high, and trying to get your opponents tossed off the ballot for having not enough legitimate signatures is just standard practice. This is just stupidly trying to associate Obama with dark and scary "urban politics" which we all know is uniquely corrupt, sometimes even electing black people, unlike suburban politics where there's no corruption whatsoever.
Sometimes you can have corrupt judges making bad rulings about signatures, but challenging signatures is a completely legitimate part of the process. And surprisingly doing so manages to take out incumbents fairly regularly, at least while I've been here.
