Billionaire Tom Steyer plans to spend an additional $10 million on helping Democrats take control of the House by attempting to drive up turnout among infrequent voters motivated by the idea of impeaching President Donald Trump. That will be on top of $110 million Steyer has already pledged for the November elections through his two political organizations, Need to Impeach and NextGen America, his effort to get young voters to the polls in 11 states. That makes Steyer, a former hedge fund manager, one of the biggest players in Democratic politics.