I've gotten word from seemingly informed folks that this post stating that donating money to the Kerry campaign would be unwise is, in fact, totally wrong. I'm not sure I grasp all the mechanics here but apparently there's something called the "John Kerry Victory Fund" which has a higher donation limit and which will be financing state coordinated campaigns and other important efforts. Moreover, part of what happens when the VP joins the campaign is that expenses for relatively mundane stuff like travel and security shoot way up at just the moment when you can't afford to lose a step with banal cash flow problems.
Now I think giving to a good House or Senate candidate is also a worthy venture, but the White House is, clearly the biggest prize. And there's always the DNC which has greater flexibility than anyone in particular with where the cash winds up and therefore has the ability to adjust to unforeseen contingencies.