They call GA for Trump with 0% of the vote in. Sort of like a Drudge debate poll.
Good News Rubio got over taken by Cruz in GA so he gets 3rd. Really did not want Rubio anywhere out side bronze medal zone tonight but VA screwed that up.
The pollsters do exit polls in areas that they consider bellweather districts. For the most part, they are fairly accurate. They wait until the polls close to tell their results. If its not close, I imagine that they know pretty early.