Ben Smith puts his finger on something my trip to Iowa made me understand:
For all the chatter about a re-jiggered primary calendar and jockeying from California to Michigan to Florida, the January 14 Iowa caucuses have emerged as the central battle of the Democratic primary.
Aides to Hillary Clinton, Barack Obama, and John Edwards all realize that, to varying degrees, victory or defeat in the caucuses is probably the single likeliest predictor of the nomination.
Thus it's not terribly good news for Obama that the recent LAT/Bloomberg poll (PDF) shows Clinton 28 Edwards 23 Obama 19 in the state. (Richardson's at 10 and all the others are in the gutter.) Although at the moment that poll is something of an outlier from the averages.