There's an intriguing trend in red rural farm states like New Hampshire, North Dakota, and Iowa that strongly parallels Goldwater and McGovern. Dean is kicking ass among farm caucus-goers by presenting an urbanized message. The rest of the candidates, by muddling their messages, don't seem to have the same level of fire in those states.
http://www.bopnews.com/archives/000128.html
There's a BIG CAVEAT. McGovern won the nomination by out-hustling and figuring out where all the small caucuses were, and how to win them. If a judge had a quasi-corrupt and secretive caucus in his basement at midnight with he and his wife, the McGovern people would find out about it and send three people to outvote them.
The key driver to victory in the nomination was ardency of support, not level of support. This is why McGovern and Goldwater could take the nominations, yet be crushed when the rest of the state came out to vote. This is accentuated by the caucus format.
Now, the point here is not that Dean is McGovern or Goldwater, far from it. Dean has a much stronger urban base than either of them. The point is that a trend that makes Dean look strong in rural states, and the rest of the Democrats look weak, is actually somewhat misleading. More likely, the rest of the Democrats just don't look like anything, and so won't motivate people to give up an evening to work for them.
None of this has anything to do with winning in the general election; getting an evening from 1000 people is a different, and somewhat contradictory challenge, from getting a few minutes from 300,000.