The Associated Press has called several primary races in Maryland, declaring that Gov. Martin O'Malley and Sen. Barbara A. Mikulski have topped the little-known Democrats challenging them. Former Gov. Robert L. Ehrlich Jr. has won his primary against investor and businessman Brian Murphy, according to the AP, with early results showing Ehrlich ahead by a 4-to-1 margin.

The following incumbent Democratic members of congress have also been declared winners: C.A. Dutch Ruppersberger (2nd district); John Sarbanes (3rd district); Donna Edwards (4th district); Steny Hoyer (5th district) and Elijah Cummings (7th district). Rep. Roscoe Bartlett (6th district), a Republican, has won his primary.