In NC, I have always just had to give my name and address. All the registered voters for the county are on a list, and they check that you're on there and that your address you told them is correct, and then print you out your ballot. So there is some checking, you have to be able to list a name of someone on their list and get the address for that name right. Someone could walk in and know a person who is registered's name and address, and vote as them, though, if they were trying to do such a thing and had that information. I suppose I could go vote as my neighbor if I wanted to. If you get caught that's serious trouble. I don't know how much that actually does happen, and I don't think it's a massive, widespread problem like the right claims, but it's certainly not a sensible way of doing things, when they could just ask you for your ID, and you take it out of your pocket and show it to them.