Sen. Barack Obama (D-Ill.) and Sen. John McCain (R-Ariz.) swept today’s Potomac Primaries for their respective parties, winning the District of Columbia, Maryland and Virginia.

Early returns have Obama leading by big margins, taking over 75 percent in the District, 60 percent in Maryland and 64 percent in Virginia. McCain collected 68 percent in the District, 55 percent in Maryland and 50 percent in Virginia, with his top competition, former Arkansas Governor Mike Huckabee, trailing far behind him.

With today’s win, Obama overtook Clinton for the lead in delegates to the Democratic National Convention, now holding a 1,212-1,191 delegate advantage, according to The New York Times. 2,025 delegates are needed to secure the nomination.

McCain increased his delegate total to 789, while Huckabee remained at 241. Former Massachusetts governor Mitt Romney, who has suspended his campaign, has 286 delegates.

Following the announcements of their respective victories, Obama and McCain took to the podium to address supporters, media and voters.

“The cynics can no longer say that our hope is false. We have now won east and west, north and south, and all across the heartland,” Obama said from Madison, Wisc.

Clinton, who, like Obama, did not stay in the area for the results, was already campaigning in Texas tonight for the state’s March 4 primaries.

McCain made several references to Obama in his speech at Arlington, Va.

“Hope, my friends, hope is a powerful thing. I’ve seen man’s hope tested in ways that many will never experience,” McCain said. “My hope for our country resides in my faith in the American character.”

This year’s local primaries took on unusual significance this year, as neither race has been completely decided.

There was speculation that some District residents would be discouraged from voting because D.C. is not represented in the Senate.

But at the Duke Ellington School for the Arts, the closest to Georgetown University, some long-time residents said the turnout this year was larger than in previous elections.

Poll workers at Duke Ellington said the station had seen a relatively high voter turnout, with 618 votes cast by 3:00 p.m. and an expected 1,000 votes by the end of the day.

“I’m thrilled by the turnout here,” said Georgetown resident Stephany Knight.

Obama campaign worker Justin Charity (COL ’09) said the Potomac primaries may be among the most important primaries in the 2008 election.

“Interestingly enough, Virginia and Maryland will probably end up having more of a say than Iowa or New Hampshire for the Democrats [in this election],” he said.