You might try a URL "shortening" service like Bitly to create a more manageable link to the petition: https://bitly.com/

It basically acts as a forwarding service and I think it also gives you a management console where you can see how many hits are coming thru and where they are coming from. Doesn't cost anything for the basic service last I checked.

There are several other URL "shortening" tools, but the names escape me at the moment.