After winning the primaries in Virginia, Maryland and the District of Columbia, Barack Obama has become the front-runner for the Democratic nomination.
He has won more states, more delegates and more raw votes than Hillary Clinton. He has also raised more money than she has so he is better able to compete moving forward.
After a clean sweep this weekend and another clean sweep Tuesday night he has her beat in the most elusive metric: He has more momentum.
He may be just a freshman in the Senate, but the Illinois senator has proven he belongs on the varsity team.
"We won the state of Maryland. We won the Commonwealth of Virginia," Obama said in a victory speech Tuesday night. "And though we won Washington D.C., this movement won't stop until there's change in Washington. And tonight we're on our way."
He is no longer just standing toe-to-toe with Clinton, he is beating the New York senator and vowing to take the race all the way to the Democratic convention.
Baltimore voter Anwar Young believes that Obama's momentum is a force to be reckoned with.
"It can't be stopped," Young said of Obama's momentum. "It is like trying to step in front of a locomotive. It's inevitability. And I think everybody needs to get ready for it, because this is where we are going to become November of this year. Mark my words, Obama is going to be president of the United States. You can take that to the bank."
While Young is not alone in his enthusiasm, one has to take it with a grain of salt, because we've heard it all before. After Iowa, Obama seemed unstoppable.
"This train is leaving the station," Obama told supporters in New Hampshire, just after the Iowa caucus. "We're about to make history."
But just a few days later, he suffered a disappointing and unexpected loss to Clinton in New Hampshire.
Some believe that Clinton's show of emotion in a New Hampshire cafe the day before voters cast their ballots may have helped her win. Clinton alluded to the incident where she choked up in response to a voter asking her "how she does it" in her victory speech.
"In New Hampshire, I listened and in doing so I found my voice," she told supporters at her victory speech.
But Clinton seems to have lost her voice since New Hampshire. Clinton has won 11 contests but Obama has won 23 contests, more than twice as many, and nearly half the country.
Clinton not only lost eight states in a row, but the margins were huge — in Tuesday night's Potomac primary, nearly 2-1.
ABC political analyst Matthew Dowd attributes this ratio to Obama's broad appeal among diverse voter groups.
"He has built up margins among all voter groups, including voter groups that were Hillary Clinton's base. Especially white voters, especially white middle class voters," said Dowd.
Clinton at first sought to ignore Obama's winning streak. On Saturday at Virginia's Jefferson Jackson dinner, when she spoke, it was clear Obama was beating her in Louisiana, Nebraska and Washington state. But not once did she thank the voters or congratulate Obama.
Her campaign dismissed Obama's victories as "expected." Then, the very next day, Clinton's campaign manager Patti Solis Doyle abruptly resigned. And Tuesday night, her deputy campaign manager Mike Henry stepped down as well.