California Sen. Barbara Boxer's retirement in 2016 may open an opportunity for another environment-friendly Democrat: Maryland Sen. Ben Cardin.
Cardin is the third-ranking Democrat on the Senate Committee on Environment and Public Works, behind Boxer and Sen. Tom Carper of Delaware. Carper is already the top-ranking Democrat on the Homeland Security and Government Affairs Committee. If Carper stays in that position, Cardin would likely be in line to succeed Boxer in 2017.
Boxer announced on Thursday she will not run for reelection in 2016.
Cardin has long been an advocate on efforts to clean up the Chesapeake Bay, limit runoff and regulate pesticides -- making him a spokesman on water quality issues nationally. He is currently the top Democrat on the Water and Wildlife subcommittee and the Senate Small Business and Entrepreneurship Committee.