With apologies, I don't know Javascript very well at all. I'm here because I'm learning.
This is an interesting question and I did a little bit of investigation. The map is in SVG and is encoded in a file called uStates.js. You can view it here:
So, this is the basis on which you can modify into something you would like to have. Now, let's look at wikipedia. They have beautiful maps.
When you view source on that map, you will recognize a VERY similar format.
As is the same with this map...
and others too that you can seek out on your own.
I'm not doing this for you, but I can bid you farewell on your journey with a wave of a hand and a "Happy cut 'n pasting!"
But please, please, please, comply with the license of any Wikipedia source.
Timothy D. Legg