09/23/2010 08:19 am ET Updated May 25, 2011

David Koch Ousts Michael Bloomberg As Richest New Yorker

Michael Bloomberg may be the Mayor, but he's no longer the richest man in New York.

That honor goes to oil billionaire David Koch, known now as the man who's bank-rolling the Tea Party.

According to the Forbes 400, Koch is America's fifth-wealthiest person, coming in with a net worth of $21.5 billion (tied with his brother Charles). Bloomberg comes in at #10 with a net worth of $18 billion.

Koch had long been #2 in the city behind Bloomberg.

Both men have seen their fortunes grow in the past year, but as the New York Post notes, high energy prices have boosted Koch ahead of Bloomberg.

The Koch brothers were the subject of a New Yorker profile last month which revealed them as the financial backers of the Tea Party.