Romney Sweeps Through Maryland, D.C., Wisconsin

Mitt Romney has won the Republican primary elections in Maryland and the District of Columbia, results and exit polls show. Votes are still being counted in Wisconsin, which remains too close to call.

Rick Santorum, who is contesting the Wisconsin race closely, has chosen to deliver his speech at a rally in his home state of Pennsylvania, where the Republican contest will shift on April 24.

UPDATE (9:30 pm EDT): Romney has won Wisconsin, completing a clean sweep and winning all of that state’s delegates.