The amount of money spent in the 2016 election cycle is on track to double the roughly $2 billion spent in 2012. One reason is the rise of spending by millionaire and billionaire political activists on both sides of the aisle. Gwen Ifill talks to billionaire Tom Steyer of NextGen Climate, who has pledged millions on the issue of climate change. Read the transcript: www.pbs.org/newshour/bb/billionaire-climate-activist-bothering-gop-primaries/#transcript