Mark Keam, a long-serving Democratic member of the House of Delegates from northern Virginia, has resigned his seat, a move that will set up a special election to fill the vacancy in the blue-leaning district. An attorney who was first elected to his Fairfax County-based seat in 2009, Keam said in an interview Tuesday that he had stepped down to take a job in the International Trade Administration of the U.S. Department of Commerce. Keam said he will serve as a deputy assistant secretary running the National Travel and Tourism Office, which is focused on bringing foreign travelers to the...