Who is Stewart Bainum Jr.? Maryland-raised businessman whose nonprofit is in line to buy The Sun has had second careers in politics, philanthropy.

The Baltimore Sun is poised to be acquired by a nonprofit founded last month by Stewart Bainum Jr., a Montgomery County-raised business owner who has also been active in Maryland politics and philanthropy. The acquisition would include The Sun, The Capital Gazette in Annapolis, the Carroll County Times and other community newspapers in the Baltimore metro region.