One man's annual donation apparently made up 25% of the operating budget of the American Civil Liberties Union. And that guy, David Gelbaum, had a bad year. So... hope you didn't need to sue the government in 2010.

Gelbaum gave the ACLU $20 million, anonymously, every year. But he will be unable to make that donation this year, forcing the organization to scramble to solicit donations that they'll have to share with state chapters.

Gelbaum is an ex-hedge funder who retired a couple years ago to become a reclusive investor in green technology and a full-time anonymous philanthropist. He is the co-trustee of the secretive Quercus Trust, which has invested in a whole ton of green tech concerns. He loves immigrants, the environment, civil liberties, and shiny, shiny fabrics.

What little anyone knows of him comes from a 2004 L.A. Times piece that revealed his charitable donations to environmental and conservation groups.

Gelbaum was born in Minnesota and moved with his math professor father to California at a young age. He now lives in Newport Beach, Orange County, and his money has "preserved hundreds of miles of wildlife corridors across mountains and deserts" in California.

According to OpenSecrets.org, Gelbaum has been donating to Democratic candidates and the Sierra Club since the '90s, with donations to Loretta Sanchez, Barack Obama, Mark Udall (in 1998), the DSCC, DNC, DCCC, Hispanic PAC USA, and a dozen other congress members and candidates. None of which is unusual for a wealthy California liberal.

But the fact that he actively shunned any publicity whatsoever for his frankly staggering donations to the ACLU and the Sierra Club and others? That is a bit unusual! For a liberal philanthropist, anyway!

And with his giant checkbook comes influence: many Sierra Club members wanted the organization to come out against illegal immigration. Gelbaum, whose wife is a Mexican-American, and who bankrolled the court fight against California's Proposition 187, made sure it didn't even get discussed.

So if David Gelbaum has a bad year, the civil rights and environmental movements have a bad year. And it looks like Gelbaum had a bad year.

How did he make his money in the first place? According to the Times, he "was a math prodigy who parlayed his talents into a highly lucrative three-decade career using mathematical formulas to pick stocks and bonds for wealthy investors in hedge funds." They report that he was hired by Edward Thorp to do analysis for Princeton-Newport Partners, until that firm went belly-up in a scandal. According to Fortune:

From 1989 until 2002, Mr. Gelbaum performed quantitative modeling for stock price returns and derivative securities for TGS Management, and from 1972 until 1989 he worked at Oakley & Sutton in a similar capacity.

Oh god, he was a quant! Doesn't that make this whole thing his fault?