The Democratic Party will either go the way of the Whigs, or undergo a profound metamorphosis whereby the current leadership of the party (DNC, the Clintons, U.S. Senators, etc.) is replaced with anti-Corporate leadership.
The short of it is that the Democrats have resoundingly won their struggles of the twentieth century. Now, with their work done, it might be time for them to retire.
The longer story begins by observing that the primary causes of the Democrats during the past century were progressive in nature. During the first half of the century, the Democrats lifted up the working class of America. During the second half, to their list of progressive achievements, the Democrats added the liberation of Jews, women, people of color, and gays. For good measure, the Democrats also tossed in green consciousness.
How do we know they won these struggles? We know because the party that had opposed the Democrats every step of the way during the past century has now beaten the Democrats at their own game. Which party was the first in the twentieth century to nominate a true "commoner" and see him elected as President? (Truman doesn't count because he "inherited" the presidency from Roosevelt.) Which party was the first to appoint a woman to the Supreme Court? The first to appoint an African American as Secretary of State? The first to appoint a woman (an African American one no less) as National Security Advisor?
Blue brought them into the tent, and it did so in the face of a century of stiff Red opposition. But once Blue got them inside the tent, it was Red who invited them (or at least a handful of them) up to the podium. Next up: the first Latino Attorney General. How soon before Mr. Bush appoints the first openly gay [fill-in-the-position]?
Now, of course anyone can cite plenty of evidence that the Democratic struggles on behalf of labor, Jews, women, people of color, gays, and the environment are far from over. I won't argue that one with you.
What I will argue is that whatever systemic national issue you can raise with respect to those groups, the systemic national issue of Corporate domination of nearly every aspect of American life trumps your issue. At least it trumps it measured on the scale of danger to those groups. This is because the Corporate danger is deadly and it does not discriminate between these "disenfranchised" groups and their "enfranchised" counterparts. Corporate harm is an equal opportunity scourge.
If this is true, couldn't the Democrats simply pick up the anti-Corporate struggle? My answer is: they can't.
My facile reasoning goes like this: Money is the lifeblood of Corporations. And as anyone who followed the 2004 election can observe, the same lifeblood courses through the veins of Red and Blue. Collectively, Messrs. Bush and Kerry raised $699 million and change for the 2004 campaign. (Sheesh, that even sounds like a Corporate price tag. I mean why not just call it $700M?)
The political party which takes up the anti-Corporate struggle will need to function on something other than money. Cause big money won't be coming from Corporations. And whatever money the anti-Corporate party raises, the Corporate-sponsored party will raise many times that amount. This is because Corporations have the money of God (assuming He/She exists and if so, would have anything to do with money).
Can the Democratic Party make the transition from Corporate lifeblood to a new blood? I doubt it. And even if the party does survive to make this transition, it won't survive in any currently recognizable form.