Don't you have to be a registered voter to submit an absentee ballot?

[Oilwellian]

Correct me if I'm wrong, but I thought you had to be a registered voter before you could submit an absentee ballot. According to Keith Olberman, absentee ballots are the reason why there were an additional 93,000 votes than number of registered voters in the greater Cleveland area.

The punch, of course, is the explanation that the 29 more-votes-than-voters precincts in greater Cleveland appear to have been caused by the addition of Absentee Ballots. The total difference between registered voters and votes (93,000) might be explained by that process, but it does little for one’s confidence in the whole result from Ohio.

http://www.msnbc.msn.com/id/6210240/