Here is a good video:
You would need to get Latitude/Longitude data for all the cities in NJ and follow the steps in the video to map them.
+1 -- the challenge is getting "Lat/Long" for each object that you want to plot on the map. (I had to built that logic in our database backend and ended up using 3rd party API to get the lat/long for each address)
Once you have lat/long, it's pretty straightforward!
And map can be zoomed in and gives enough detail -- our business users have been pretty happy with that.