The super PAC funded by a former hedge fund manager turned environmental activist has made its latest move in the Massachusetts special Senate election, donating $250,000 to another super PAC run by the League of Conservation Voters, which supports the primary campaign of Rep. Ed Markey, D-Mass., according to Federal Election Commission reports.

Tom Steyer, a billionaire based in San Francisco, has shaken up the race by giving at least $750,000 to the NextGen super PAC, to which he is the sole donor so far. Steyer's ire is aimed at Markey's opponent, Rep. Stephen Lynch, D-Mass ...