From our own Pollster.com linky:
The best way to consider what “the polls” say about the Democratic contest is to look at our Iowa chart, though I would recommend focusing as much on the points (representing results from individual surveys) as the trend lines. Consider this screen grab from the 2007-only chart, which shows the Iowa results since late August for Clinton (purple), Obama (yellow) and Edwards (red). The trend lines draw on earlier data not seen in the snippet, but if you focus on the last month it is hard to see much of a trend from all the seemingly random noise.
By and large, the Clinton results have been slightly (but not consistently) better than the Obama results with Edwards generally trailing the two. Some of the differences stem from random noise, some from systematic differences in method. Which poll has been most “right” in recent weeks? We may never know. The best characterization, given the overlap in the ranges for each candidate, is the one that The Washington Post put on their own results: “The top three Democratic presidential contenders remain locked in a close battle in Iowa.”
Do. Not. Believe. The. Corporatist. Press!
This thing ain’t over.
Note: Bold by me.