There's variation state-to-state. In NC (1996-2012 at least), no poll workers touch ballots with identifying information in them. On entry to the polling plac

There's variation state-to-state. In NC (1996-2012 at least), no poll workers touch ballots with identifying information in them. On entry to the polling place, a sticker is placed beside your name on a physical rollbook to keep track of who has and hasn't voted. The poll worker hands you your ballot which you take to a privacy booth to mark your choices. The voter personally inserts the anonymous ballot into the counting machine. CO has universal mailings. You mail (or drop off) your ballot in a double envelope, and only the outer envelope carries identifying information. One workstation examines the outer envelope to track who voted, and a different workstation processes the anonymous ballots. It requires a little more trust on the part of the voter, but also encourages more participation.