New CNN & Zogby polls contradict DMR: What's going on?

New polls today by CNN and Zogby both put Clinton in first place.  What are the numbers and how can you explain the difference between these and the DMR poll?  More below the fold

Here's the CNN results:
Clinton 33
Obama 31
Edwards 22

And Zogby
Clinton 30
Obama 26
Edwards 25

How can the discrepancies between, on the one hand, these two polls and a half dozen other recent polls, all of which show Clinton or Edwards on top, and the DMR poll, which shows a big lead for Obama?

Well, I think they are explained by what can only be characterized as the bizarre findings of the DMR poll.  Here was the turnout in 2004 Democratic Iowa caucus according to exit polls:

Iowa Democratic Caucus 2004
Total Turnout: 124,000
Democrats: 99,200 (80%)
Independents: 23,560 (19%)
Republicans: 1240 (1%)

Well, according to the DMR poll, the percentage of Independents and Republicans caucusing in the Democratic caucus this year will leap to 40% and 5%.  Projecting a turnout of 200,000 people, which would be a huge leap, this means numbers such as the following:

Iowa Democratic Caucus 2008
Projected Total Turnout: 200,0000
Democrats: 110,000 (55%) [number up 11% from 2004]
Independents: 80,000 (40%) [number up 340% from 2004]
Republicans: 10,000 (5%) [number up 806% from 2004]

Look at the increased numbers from 2004.  They are, to put it mildly, very unusual.

The DMR's projection is not impossible, but it seems to me very unlikely.