After numerous 19 turn games on level 3, a few 18s here and there, and two or three 17s; I finally hit a 16, which sounds like it may tie the record.
Starting position was Western Kazakhstan, with the Caucasus bonus by the end of turn 2. I've had that situation a few other times, but I think the real "luck" factor this time was that each AI failed to get a card piece on one turn. Had any one of them been able to get reinforcements at the beginning of turn 16, I wouldn't have been able to knock them out on that final turn.
I don't think it's possible, but has anyone had a 15 turn win on level 3?
Finally - Single Player Level 3 in 16 turns!: 12/20/2011 05:57:37