Barack Obama piled up three more commanding wins Tuesday -- in Maryland, Virginia and the District of Columbia -- establishing the onetime underdog as the front-runner in the Democratic presidential race against Hillary Rodham Clinton.
Obama stacked his victories on top of several wins over the weekend, pushing his record to 8-0 since he and Clinton in effect fought to a draw last week on Super Tuesday. Significantly, the Illinois senator also pulled ahead of Clinton in delegates to the party's national nominating convention, according to a tally kept by the Associated Press.
Combined, Obama's performance put a strong breeze at his back and increased pressure on Clinton, who faced new campaign turmoil Tuesday, to reverse her fortunes when six more states pick delegates over the next three weeks.
On the Republican side, Sen. John McCain of Arizona moved closer to clinching the nomination, winning all three contests over former Arkansas Gov. Mike Huckabee and Rep. Ron Paul of Texas.
But McCain struggled in Virginia, where a heavy turnout of evangelical Christian voters helped buoy Huckabee, an ordained Southern Baptist minister. The former governor also overwhelmingly won Virginians who identified themselves as conservatives, pointing to continued resistance toward McCain among many of the GOP's base voters.
Obama's victories marked the first time in six weeks of balloting that either Democratic candidate has strung together so many successive wins. For a time, they traded triumphs every week or so. But Obama started to broaden his support in the last few rounds; he continued to make inroads Tuesday.
He carried Latinos in Virginia and women and lower-income voters in Virginia and Maryland; all have been vital constituencies for Clinton. At the same time, Obama continued to show tremendous strength among African Americans as he bids to become the nation's first black president; on Tuesday, he won nearly 9 in 10 black votes in Maryland and Virginia, according to exit polls conducted for a consortium of news organizations.
Obama easily bested Clinton in both states among Democrats most concerned about the economy and the war in Iraq. Clinton edged Obama among those most concerned about healthcare.
"Every week that goes by, people get a little more comfortable with him, and he gets a little stronger," said Paul Maslin, a Democratic pollster not aligned in the race. But, he cautioned, "this thing is not over."
Indeed, many Democrats confessed to a hard time deciding between the two.
"I almost didn't vote at all because if you're perfectly even, how do you choose?" said Marc Shapiro, 39, an international development consultant in Falls Church, Va., an upscale suburb of Washington. He wound up casting his ballot for Clinton.
"I went with the issue of who's ready to serve from Day One," said Shapiro, picking up on a favorite Clinton talking point.
Steve Selby, 56, a public policy professor at Michigan State University's Washington semester program, voted at the same Falls Church apartment complex. He praised Clinton as a "very strong candidate" he could happily support in November. But he backed Obama out of "a sense of change, sense of hope."
"I find the excitement among young people very encouraging," Selby said. "I think he's generated some genuine excitement that I haven't seen since I was a kid."
For the first time, Obama pulled ahead of Clinton in the delegate count, 1,223 to 1,198, according to the Associated Press. It takes 2,025 delegates to win the nomination at the party's national convention in August.
Despite the closeness of the delegate count, Obama has seized a decided edge over Clinton in momentum. He drew huge crowds over the last several days and flexed his financial muscle by handily outspending Clinton on TV advertising in Virginia, Maryland and the District of Columbia. Over the weekend, he racked up five victories -- in Louisiana, Nebraska, Washington state, Maine and the Virgin Islands -- by crushing margins.
Clinton, by contrast, has weathered one of the roughest patches of her campaign. The day after Super Tuesday, she revealed she was forced to lend her campaign $5 million because of a cash squeeze. (Online fundraising immediately picked up, the campaign reported.)
Days later, Clinton jettisoned her friend and campaign manager, Patti Solis Doyle, in a long-anticipated shake-up that came amid increased grumbling from supporters concerned about the trajectory of the former front-runner's campaign. On Tuesday, in a sign of continued upheaval, Clinton's deputy campaign manager, Mike Henry, stepped aside "out of respect" for Doyle's replacement, Maggie Williams.
Perhaps more significant, after being shut out since Feb. 5, the Clinton campaign is bracing for more losses Tuesday in Hawaii, where Obama was born and spent part of his childhood, and Wisconsin, a state with a history of embracing government reform candidates like Obama.
Clinton is pinning her hopes on two big states that vote March 4: Ohio, with many of the economically hard-pressed voters who have rallied to Clinton's side elsewhere, and Texas, home to a large number of Latinos. In some earlier contests, Clinton swamped Obama among Latino voters.
On Tuesday night, Clinton was already looking ahead to Texas, campaigning in El Paso. Speaking as television networks were trumpeting Obama's Virginia and Maryland victories, Clinton assailed President Bush and stuck to her stump speech on education, healthcare, the environment and Iraq. She renewed her pledge to start withdrawing U.S. troops within 60 days.
"Many of you are veterans, and you know that planning to withdraw our troops must be done carefully and responsibly, but we must start," she said.
At a rally moments later in Madison, Wis., Obama called attention to Clinton's Senate vote for the war, saying America must "do more than end a war -- we need to end the mind-set that got us into war."
"That's the choice in this primary," he told the cheering crowd. "It's about whether we choose to play the game, or whether we choose to end it; it's change that polls well, or change we can believe in; it's the past versus the future. And when I'm the Democratic nominee for president -- that will be the choice in November."
Some suggested Tuesday night that Clinton needs to win Ohio or Texas -- if not both -- to keep her campaign alive.
"When momentum takes over in a nominating process, it's really hard to stop it. It becomes a self-fulfilling prophecy," said Tad Devine, a veteran Democratic strategist watching the primary from the sidelines. The sense of a tidal shift could be particularly important among "super delegates" -- the party elites who could decide the nominating contest -- because "people like to be with a winner," Devine said.
On the Republican side, McCain was looking Tuesday to recover from a pair of embarrassing weekend losses in Kansas and Louisiana, where Huckabee prevailed even though McCain appears all but certain to win the GOP nod.
Appearing at a victory rally in Alexandria, Va., McCain thanked voters for "a clean sweep of the Chesapeake primary." He also commended Huckabee for running a spirited campaign. "He certainly keeps things interesting -- maybe a little too interesting at times tonight, I must confess," he joked.
Turning to his Democratic rivals, McCain said, "We know where either of their candidates will lead this country, and we dare not let them. They will paint a picture of the world in which America's mistakes are a greater threat to our security than the malevolent intentions of an enemy that despises us and our ideals."
After assailing the Democratic candidates, McCain puckishly ended by swiping one of Obama's lines, declaring, "I am fired up and ready to go!"
In Little Rock, Huckabee vowed to fight on, predicting success in Texas, North Carolina and other states.
McCain had 821 delegates; former Massachusetts Gov. Mitt Romney -- who quit the race last week -- had 288; Huckabee, 241; and Texas Rep. Ron Paul, 14, according to the Associated Press. It takes 1,191 delegates to win the GOP nomination.
Barabak reported from San Francisco and Finnegan from Falls Church, Va.