A lot of people, obviously, including Bill Gates Sr. and a majority of Washington Poll responders.

But who's actually putting money behind Gates's proposed initiative to create an income tax for those making more than $200,000 a year in Washington State?

The latest PDC filings begin to answer that question, and there are some interesting names on the list of contributors.

Gates is there, of course, putting in $50,000. Health care unions are also big backers—no surprise since the initiative would help the state spend more money on health care—with SEIU putting in over $250,000.

An infantry officer from the U.S. Army has put in $50. Familiar donor names like Alhadeff and Bridge are in for thousands, as is Ruth True, owner of Nube Green and co-owner of Western Bridge gallery, who put in $5,000. And there's even one journalist on the list: Michael Kinsley, who, like his wife Patty Stonesifer, is in for $5,000.