This post, originally published in April, has been updated with the latest fundraising numbers. 

Tuesday's congressional election in Georgia has officially become the most expensive congressional election in history, and it's largely because Democratic donors want to stick it to President Trump.

Jon Ossoff, a Democrat who is polling with a narrow lead over Republican Karen Handel, brought in a mind-boggling $20 million over the past three months, as of last week. That dwarfs the last pre-election quarterly hauls of every single congressional campaign from the entire 2016 cycle. Campaigns in competitive races, on average, took in just 2.5 percent of Ossoff’s total over a comparable period.

Although the numbers are staggering, it’s perhaps not surprising that Ossoff, who has never held elected office and, at age 30, would be the youngest sitting member of Congress, is attracting national attention — and the money that comes along with it.

The election offers a potential referendum on Trump's and Republicans’ performance since they took control of Washington.

Democrats, emboldened by a Trump approval rating quickly falling below 40 percent, are hungry for a big symbolic victory. And Georgia’s 6th District is a great place to try to score it. The suburban Atlanta district is affluent, highly educated and favored Trump over Hillary Clinton by only 1.5 percent after favoring Mitt Romney by more than 20 points the previous election — meaning it's fertile soil for what Democrats could cast as a rebuke of Trump. Helping matters is the fact that there are no competitive Democrats in other congressional races to take donors’ checks.

But even when you factor in all of those exceptions, the fact Ossoff raised 40 times as much as the average candidate in a competitive district is still stunning.

About the closest analog is the 2010 special election for U.S. senator from Massachusetts, where Republican Scott Brown narrowly beat Democrat Martha Coakley in a big upset after becoming a national cause celebre for the GOP. It was widely considered a referendum on the Affordable Care Act, then being negotiated in Congress. But even then, it was just the sixth-most expensive Senate race of the cycle.

Ossoff and Handel will face off in the special election runoff Tuesday to replace Tom Price, who became Trump’s secretary of health and human services.