And when I assisted my mother with voting her absentee ballot, she had to specifically request it and it was sent to her by US Mail. It was the same physical ballot as would be handed to me at the polling place, and it too had a marking on it indicating it was an absentee ballot in lieu of the voting order number, along with the initials of both the city clerk and what I think was the deputy clerk. She marked the ballot herself while I stood by and acted as a witness. Then, after marking it, it was placed into a dark brown-paper envelope and sealed. On the outside of the envelope was a place for her to sign, and also the registered voter acting as witness (me, in other words) to attest that the person submitting this absentee ballot had marked it themself without any interference, coercion, or directions concerning how to vote from anyone else, including me, and then sign that. And if someone DID have to mark the ballot for her (let's say she was legally blind, or unable to grip or manipulate the pen) there was yet another section for THAT person to complete and sign to certify that he/she had marked it in accordance with the voter's preference. This was then returned to (in our case) the city clerk's office, either by US Mail or by hand-delivery to the clerk's office, which is what I usually did.
After that, it was my understanding that the ballots were separated, based on the address of residence of the absentee voter, into boxes for the various voting precincts and held, unopened, at the clerk's office. On election day they were sent to the appropriate precinct's polling place, where they were then re-inspected for the correct information on the outer envelope, and then opened. The ballot was checked for the appropriate verification marks and initials, and then fed into the voting machine by the poll workers, of which there were at least three present. I must admit, in the interest of full disclosure, that once I had surrendered the sealed absentee ballot into the hands of the city clerk, I never actually witnessed any of the process outlined above — but there were enough articles in the local newspaper and on TV as to the care and feeding of absentee ballots that I feel 100% sure this was in fact the procedure and it was scrupulously followed.
So while there might be a possibility of election fraud by somehow getting one's hands on a sufficient supply of absentee ballots, it would involve a helluva lot of work and effort to do it in such as way as to not arouse suspicion and properly cover one's tracks. I'd personally be more worried about someone, like the AG of Georgia, acceding to Trump's request to "find me 11,700 votes" and do it by having 12,000 or so ballots for the other guy suddenly disappear into a black hole or the Atlanta Triangle or something like that.
-"BB"-
