WASHINGTON — Is Hillary Clinton momentum-proof?
That pivotal question looms large over the political landscape, now that Barack Obama appears on the verge of breaking the long stalemate in the Democratic presidential campaign.
The Illinois senator's sweep of primaries Tuesday in Maryland, Virginia and Washington, D.C., brought his unprecedented winning streak to eight after five weekend victories. It could easily stretch to 10 if he wins Hawaii and Wisconsin on Feb. 19.
That dramatically changes the story line that's defined the race so far — one in which he and the New York senator take turns winning, always remaining roughly equal in the number of delegates each has won and denying each other any hint of momentum.
Indeed, Obama now appears to be at a tipping point where all the good news is his and all the bad news is hers. Beyond Clinton's string of recent losses, she's also replaced her campaign manager and deputy manager and loaned her campaign $5 million from personal funds.
Whether these developments turn Obama's campaign into a bandwagon in which Democratic voters start piling on — the more historically normal pattern at this stage — will determine whether Obama seizes front-runner status or the two keep slugging it out into the spring.
Obama's camp on Tuesday resisted the suggestion of momentum but did argue that he's poised to start pulling ahead of Clinton in the all-important competition for the delegates who will select the nominee at next summer's Democratic National Convention.
"I don't think it's so much about momentum as the reality of the math," campaign manager David Plouffe said Tuesday.
"We have a healthy pledged-delegate lead. ...If we continue to do that, mathematical reality sets in and it becomes harder and harder to overcome."
Obama's lead among delegates pledged to support either candidate at the convention remains small. Entering Tuesday's "Potomac Primary," he trailed in the overall count when it included the support of "super delegates." Clinton had the edge among those delegates, party leaders who are free to support anyone they choose.
But Plouffe said Tuesday's results would add to Obama's lead in pledged delegates, which emerged with his five victories last weekend, and would start to push him into the overall lead.
"I think it will be looked back on as the decisive weekend for the nomination," Plouffe said Tuesday.
Clinton now is in the unusual position of insisting that she can survive a three-week stretch of up to 10 straight losses to Obama, and that she will then win Ohio and Texas on March 4.
Clinton spokesman Howard Wolfson basically wrote off most of February, trying to shift attention to March 4, when Clinton thinks she can win again because Democrats in Ohio and Texas more closely match her coalition of supporters.
"It's going to be a better month for Barack Obama than it will be for us," Wolfson said. "We believe next month will be a better month for us than it will be for him."
If that strategy sounds familiar, it is. Republican Rudy Giuliani tried it when he basically wrote off January contests in Iowa, New Hampshire, Michigan, Nevada and South Carolina to focus on Florida.
One aide even infamously boasted that Giuliani could survive those early losses because he was "momentum-proof."
There are big differences between Giuliani and Clinton, however. She's actually won already. She has an edge over Obama in support from super delegates. And she won't fade into the background as Giuliani did while other Republicans contested the early states.
But eventually she does have to start winning again.
On the Republican side, Arizona Sen. John McCain moved closer to locking up the nomination as former Arkansas Gov. Mike Huckabee approached being mathematically locked out despite a surprisingly strong challenge in Virginia.
McCain entered the day with 729 of the 1,191 delegates needed to win the nomination and looked to pick up most of the 116 awarded in Maryland, Virginia and Washington, D.C. Virginia and D.C. award GOP delegates on a winner-take-all basis, while Maryland awards its delegates to the winner of each congressional district.
Huckabee started Tuesday with 241 delegates. If shut out Tuesday, he would need to win 950 out of the 1086 delegates yet to be selected to triumph over McCain.
Huckabee insisted anew Tuesday that he'll keep running, if only to give a choice to Republican voters in states yet to be heard from, such as Ohio and Texas.
Said Huckabee Tuesday: "Why should we disenfranchise voters from the remaining states?"