General quiz on the items on the ballot. If you know the issues and can articulate the general jist of the things you are voting on, you have a verifiable ID, SS Number, and are registered to vote in said precinct, then proceed to vote.

If you can't even say, let alone spell, articulate, then you can only vote in the general elections at the local level. You do not contain the mental faculity to comprehend those things which you are casting your lot for. Therefore, you have recused your right to participate.

In short, the sign reads "No mouth breathers, knuckle dragers, brainwashed regurgitating sheeple, and especially no one named Wolfgang."

Don't make me have'ta Troll ya Bro!