Here is the bigger question....how are they verifying the ballot is legit? Are they verifying the signature? how? My guess is most likely they aren't doing anything to verify the signature and instead simply rip the envelope open before jamming it into the tabulating machine. So in theory, anyone with these ballots could simply fill them out, write a fake signature (you already have the person's name from the front), date it and mail it in.

The election people are pretty light on details in terms of what their verification process is.