"Pay-to-Play" is the money engine that connects local government to businesses like contractors, law firms, engineering firms, etc. Businesses that want to do work for the local government are encouraged to contribute to the political organizations that control the local pursestrings.

How Pay-to-Play works (from Asbury Park Press) You can use the NJ Election Law Enforcement Commission's website to search for contributions to candidates or committees as well as to parties and political action committees (PAC's).

As "Pay-to-Play" is basically corrupt, there is usually an effort made to hide it. One such approach is called "wheeling", where donations to one local organization are given to another organization, and possibly a third, fourth, and so on. The intent is to hide the connection between the original donor and the final recipient.