Sen. Barack Obama (D-Ill.) swept the Potomac primaries, throwing Sen. Hillary Clinton?s (D-N.Y.) strategy of focusing on bigger states next month into question.

Sen. John McCain (R-Ariz.) and Obama won the primaries in Washington, D.C., Maryland and Virginia. With the latest wins under his belt, Obama has more delegates than Clinton for the first time since the Iowa caucuses.

As Tuesday night?s votes were still being counted, Clinton was at a rally in El Paso, Texas, vying for the Hispanic vote. Clinton seems to be using former NYC Mayor Rudy Giuliani?s strategy of trying to win in bigger states.

For McCain, the Republican front-runner, the latest round of wins was a welcome reversal after weekend losses to Mike Huckabee. The Arkansas governor vows to stay in the race, despite the seemingly impossible task of overcoming McCain's commanding lead.