Mike Scully is from West Springfield, I believe his daughter teaches in Springfield. He calls into the radio 102 morning show quite often when he's in the area.
There are actually quite a few things similar that can easily be seen as familiar to Springfield MA. For example, the bridge is remarkably similar to the Memorial bridge. Several episodes mention the Springfield Armory, which Springfield MA is famous for and a national historic site. Mayor Quimby is obviously modeled after certain MA politicians, etc.
Not saying it's the model for the whole town, but to think that Mike injected a bit of his local home isn't a stretch.