Right now this is shaping up to be Hillary vs. Gore or Hillary vs. Feingold. Should Gore run, he will win the nomination. Feingold will only be a contender if Gore does not run. Edwards comes in second as anti-Hillary.
Mark Warner has no chance. He is unable to inspire passion in the Kossites and the argument that "he's the most electable" never goes down well with them. He is not attractive or charismatic and sounds too much like this guy: http://www.oddtodd.com/index2.html
If the war in Iraq suddenly ended and it ceased to be an issue, then he might have a chance, but right now anti-war is all the Dems want to hear.
In the end, I predict that it'll come down to a showdown between Hillary and Feingold / Gore. The Republican nominee will be either Giuliani or Romney. Bank on it.
Vander Blubb? More like Vander Flub. Amirite?