Having one party in control of most major cities, where most crime is, for 50+ years now is working wonders.
How come that the entire political scene on all levels collapses into just two poles, with the predictable result that many places are de facto one party places?
Why doesn't America have local Ross Perots in various corners of the country, starting their own political parties specific for one place only?
In a multiparty system, it is much more normal to be a swing voter.