Billionaire Tom Steyer Launches 2020 Presidential Campaign

Tom Steyer speaks onstage during The People's State Of The Union at Town Hall in New York City on Jan. 29, 2018. Roy Rochlin/Getty Images

Billionaire investor and liberal activist Tom Steyer reversed course on July 9 and said he would join the crowded field of Democratic 2020 contenders, months after he stated previously that he wouldn’t run for president.

Steyer is one of the loudest voices pushing for President Donald Trump’s impeachment.