Having lived there, a lot of you do not understand NJ. The election process is not particularly corrupt, the way Chicago or Michigan are; it's not a model of perfection, but it is pretty much on the up-and-up. Everything else is corrupt, though, from the way construction contracts are done, to trash services, to unions, to municipal payrolls, to the parties themselves. The major sources of it are not so much party loyalty as plain old money, nepotism, institutionalized graft (Enabled by institutionalized inefficiency), and organized crime.
The big central-authority cities are outside Jersey, it is a vast network of densely-packed small-to-moderate-sized towns, including a lot that are bedroom communities of Philly and NYC, with a couple of moderate-sized cities like Trenton and Newark thrown in the mix (Now Newark is pretty crooked, but it just isn't big enough relative to the densely-packed towns and small cities in the rest of the state to matter all that much).