Who Put This Huge Database of U.S. Voting Records Online?

[MH1]

4. My understanding is that MOST of what you list, IS public information.

I can go to my county Bureau of Elections, and for a processing fee, get that data for all registered voters in the county. Except birthdate, I think. The output I've seen only has age. But everything else is there. (I haven't gotten around to doing that yet because I don't have enough time on my hands to set up a competitor to VAN. Yet. But I have asked and this is what I was told.)

How else does a candidate's oppo team find out that her opponent never even showed up to vote until a couple years ago when they started thinking about running this race?