Two weeks ago, the conventional wisdom (a clear oxymoron) was that Dean had the nomination sown up. Now they say Kerry has it. I didn't buy it then and I don't buy it now.
In 2000, John McCain stomped Bush in New Hampshire, and Gore was tied with Bradley -- and much for the same reason: In NH, people can register on voting day, and independents can vote in party primaries. In 2000, the centrists all voted Republican and for McCain (something that was seen in other cross-over states), and the core Democrats went for the more leftist Bradley (incidentally causing Gore to move left).
This time there was no race for the Republicans, so all those independents voted in the Democrat race, and against Dean. Even Lieberman helped, as his 9% was much better than his poll numbers.
Iowa, as always, is too parochial and too weird a system to draw conclusions from.
So the real test will be next week when 7 states vote, several of which will have closed party primaries. Dean needs to win some of these, to be sure, but Kerry needs to show he can win a primary without independants. Further, Kerry needs to show that he can win in the south and west, which looks mighty iffy right now. My take is that the results will be all over the place, with Kerry, Dean and Edwards each winning some. Only Lieberman and Clark look to be gone by mid-February. Sharpton or Kucinich would be gone too, if either was in this to win, but they're not.
Note aside: Best line I've heard so far: Against Bush, who would vote for Kerry who did not vote for Gore?