By Aaron Weiss

In addition to Open Secrets, The NY Times campaign finance site is an amazing tool for comparing candidate fundraising.

The first thing to keep in mind when looking at the Times map: the circles showing where a candidate's donations come from only include donations larger than $200. That affects Obama's numbers more than anyone else: 28% of his money came from under-$200 donors, so that cash doesn't show up on the map.

Clinton, on the other hand, raised more than half her money in $2,300 checks, meaning those donors are maxed out. A large number of them are maxed out through the general election as well -- 20% of her $63 million can't be spent until after the primary. Only 7% of Clinton's money came from under-$200 donors.

On the Republican side, it's a similar, though less extreme, story between Romney and Giuliani. 58% of Giuliani's money came from maxed-out donors. Only 33% of Romney's money came in maxed-out, the lowest percentage among the top 4 fundraisers.

What does this mean? Obama and Romney can both tap their existing donor base for lots more money. Giuliani and Clinton have to find new donors.

Coming up: Oregon vs. Washington in the donation race.