Multiple sources now...

http://www.telegraph.co.uk/news/2017/06/14/baseball-shooting-james-t-hodgkinson-gunman-opened-fire-congressional/

"Hodgkinson was vociferous on social media about his dislike for Donald Trump and reportedly volunteered on political campaigns for Bernie Sanders.

Charles Orear, 50, a restaurant manager from St Louis, told the Washington Post he met him during a campaign in Iowa.

“He was this union tradesman, pretty stocky, and we stayed up talking politics,” he said. “He was more on the really progressive side of things.”