Gallup has been choosing the “undecideds” for town-hall debates since at least 1996. The transcripts show the moderator calling on questioners by first and last names. Should be easy for FReepers to quickly discover how they all contributed to O’s campaign:)
It’s easy to spot the plants. For instance, Frank Luntz’s groups always have at least one person on each side who obviously lied to the interviewers. You can tell because instead of actually giving an honest answer they come out hard for one side or the other, sometimes regurgitating talking points.