ANNAPOLIS, Md. — As a bill legalizing same-sex marriage in Maryland hurtles toward a vote in the legislature this week, a coalition lobbying for its passage has focused much of its efforts on a group of Democrats who could potentially scuttle its success: African-Americans.

ANNAPOLIS, Md. — As a bill legalizing same-sex marriage in Maryland hurtles toward a vote in the legislature this week, a coalition lobbying for its passage has focused much of its efforts on a group of Democrats who could potentially scuttle its success: African-Americans.