According to a non-profit organization called MAPlight.org, which has all kinds of information on who is contributing to what politician or bill, there are several noted stock traders and investors who have made political contributions. Doing a search on famous billionaire and stock trader Warren Buffett, head of Berkshire Hathaway (BRK-A) (BRK-B), you would discover that he made a couple of contributions during the last two years.
He contributed $2400 to Byron Dorgan, Democratic Senator in North Dakota, and anther $2400 to Harry Reid Democratic Senator in Nevada.
By the way, in 2007, he contributed to the election of Hillary Clinton and Barack Obama.
As for other noted investors and traders, in the last couple years, George Soros has contributed to Paul Hodes (Democrat NH House), William Owens (Democrat NY House district 23), Kirsten Gillibrand (Democrat NY Senate district), Howard Berman (Democrat CA House district 28), Michael Bennet (Democrat CO Senate district), Thomas Perriello (Democrat VA House district 5), Charles Schumer (Democrat NY Senate district), and Donna Edwards (Democrat MD House district 4). Soros also contributed to the Obama campaign in 2007.
Carl Icahn made only one contribution in the last couple years, to Max Baucus (Democrat MT Senate district).
T. Boone Pickens also only made just one contribution, to Dan Boren (Democrat OK House district 2).