The state of North Takoma
. The capital and largest city in that state is Capital City
I live in a Springfield which has several similarities to the Simpsons' hometown, but the "Where do the Simpsons live?" debate is a futile one. The town is fictional, and meant to represent "Anytown, USA". Springfield is, after all, one of the most common town names (if not the most common).
The "Northern Kentucky" reference was just to shock people, as the topic has become so controversial that it needed some deflating. Covering up the state name has been an inside joke so long that anyone who still thinks they can somehow derive Springfield's actual location is out of his or her mind, or maybe just tired of looking for the Loch Ness Monster.
There is enough evidence to make a case for or rule out any of the 50 states.