Richardson went in to the caucus in 2008 with 7% according to entrance polls; he ended up with 2.1%. O'Malley I think has somewhat more concentrated support, so maybe he gets 3%. Even if the remaining 4% splits 3:1 for Bernie, it's not nearly enough here. So I think the decisiveness of O'Malley supporters is a bit exaggerated.
The decisiveness is predicated on the expectation of an extremely close finish.
Anyway, I don't think O'Malley is actually at 7%. PPP has some quirk in their methodology where candidates at 0-1% always poll higher for some reason. I distinctly remember Webb and Chafee frequently getting 3-5% in PPP polls when they never cracked 1% in any others.
