Follow them out to their vehicle and photograph the license plate. That will track them down to where they actually live and offers a more solid case. The problem is the damage is allready done and our guys lose.
Take your camcorder with you, use the telephoto setting and stand outside of the polling place limit. Among other things, put it on YouTube ASAP. With all the personal electronics so prevalent, this ought to be almost real time.
Had to place a call to the Orange County Registrar of Voters.
The incompetent poll workers at my polling place were allowing people to register and vote today! California State law is you must be registered no later than fifteen days prior to the election, or October 22. The person I spoke to said she would make a notation next to that polling place, I asked if maybe someone should give them a call and tell them law and she went silent.