Ben Cardin has won the endorsement of the The Washington Post over his primary opponent, former NAACP head Kweisi Mfume:

For the state's Democrats, the Sept. 12 primary is an embarrassment of political riches: Both candidates are substantive, serious and broadly experienced; either would make a fine senator; and each dwarfs the other candidates on the primary ballot. Our choice is Mr. Cardin, whose mastery of public policy, pragmatic bipartisanship and even-keeled determination have made him a superb lawmaker.

Read more about this electrifying and important race here and here.