A quick reaction to last night's and this morning's events:
I don't think that Dean supporters will move en masse to one particular candidate, even if Dean offers a strong endorsement of one. We are too disparate a bunch - made up of economic moderates, new england Republicans, disaffected Naderites, pragmatic leftists, Gore and Bradley supporters, and so many interest groups on the left - to ever agree on one replacement for the man who was able to bring us all together. And obviously a lot will have to do with Dean's (and Trippi's) own actions in the coming weeks and months. That being said, here's where I see Dean's support moving for super Tuesday and the rest of the primaries:
Edwards: there seems to be a genuine desire on the part of many Dean-supporters to challenge Kerry no matter who the opponent. And Edwards is the last one standing for the ABK crowd. Roughly
30% of Dean's support goes to Edwards, which would increase if he endorses. Mostly the hardcore pragmatic Deniacs who despise Kerry for his campaign, the centrists who responded to Dean's populist message, and those who would otherwise go to the frontrunner but truly believe Edwards is more "electable".
Kerry: Most of the Dean supporters who would go to Kerry, already have done so. It was this massive shift of voter opinion that put Kerry where he is today - in most states, he and Dean have reversed positions in the polls from a month or two ago. So Kerry only gets about 15% of the remaining Dean supporters - those who are hardcore ABB and believe Kerry is the strongest candidate vs. Bush, those who haven't paid enough attention to the campaign to know about Kerry's dirty tricks, the soft support who would have voted for Kerry in 2002, Dean in 2003, and would revert to Kerry in 2004. So it's a net gain for Edwards, enough to make him super-competetive on Super Tuesday.
Kucinich/Nader: I think this group is being vastly underestimated. Much of Dean's support came from people marginalized by the political process, many of whom were Naderites in 2000. Many on the left see little difference between Kerry and Edwards and would pull the lever for Kucinich in a primary that they don't see as mattering any more. I'd guess about 15% of Deniacs would do this. In the general election, if Nader runs, this group will likely be Nader's target. It will be interesting to see how Dean's visibility and leadership affects this group throughout the spring and summer. My guess is, it won't end up helping Nader much, as this disaffected group will have time to come to terms with things and either stay home or vote for the Democrat in November (and Nader, without the Green party, will be a much weaker candidate this time around, more like 1996 than 2000). But Kucinich could be the immediate beneficiary and may bounce up to double-digits in some of the coming primaries, especially CA.
Drop Out: It's up to Dean to try to keep his supporters involved in the political process. But for the immediate future I can see roughly 40% of Dean's supporters taking the next few months off, paying attention to Dean's new organization, his new focus (whether it's on Congress or policy or something else entirely), but staying home on primary day. Many may stay home in November as well. But a fair amount will not work for any candidate, and come back and vote for the Democrat in November.
So I see Edwards as the immediate beneficiary, followed by Kucinich. And, in the end, in November, a lot will depend on Dean himself.