That's the primary last time. To make a long story short, national horserace polling data right up to the day of the Iowa Caucus had no informational value whatsoever about the outcome of the nomination race. That's not to say that the precise same post-Iowa bandwagon pattern is likely to repeat this year. It does, however, indicate that massive shifts of sentiment are possible (which is understandable, since the race contains a bunch of people I have basically warm feelings toward and I'm clearly not the only person who feels that way) right up until the last moment.
This article available online at:
http://www.theatlantic.com/politics/archive/2007/05/early-polling/42610/
