San Francisco's Tom Steyer is a force in progressive politics.   A successful former professional investor, Steyer is now dedicated to addressing climate change, inequality, immigration reform, and voter registration and civic engagement.  He backs his advocay with personal philanthropy as well as the efforts of his grassroots organization, NextGen America.  You may one day see his name on a ballot, as well, and he discusses all this with KCBS Radio's Jane McMillan.