(Agencies)
Updated: 2008-02-13 08:56

WASHINGTON -- Democratic Sen. Hillary Rodham Clinton has found a lot of ways to explain her string of losses to Sen. Barack Obama.

A voter leaves a polling station in Arlington, Virginia in this undated photo. Barack Obama looks likely to trounce Hillary Clinton in a trio of Washington-area Democratic primaries and build his lead over the former first lady in their fight for the party's White house nomination. [Agencies]

Caucus states, the former first lady says, are undemocratic and cater only to party activists. Southern states, like Louisiana, have "a very strong and very proud African-American electorate" naturally predisposed to favor a black candidate. And so-called "red" states like North Dakota, Idaho and Kansas -- all of which Obama won on Super Tuesday -- will never choose a Democrat in the general election anyway.

By this logic, only certain states really matter, such as New Hampshire and New Jersey, states that Clinton has won. Or Texas and Ohio, states she must capture to stay in the race.

The list of excuses is long, but the justifications are wearing thin as Obama was expected to win primaries in Maryland, Virginia and the District of Columbia on Tuesday after a four-state sweep last weekend plus the Virgin Islands. All the contests Clinton has suggested don't count are proving in size and scope that they do.

"Every day the numbers show the true state of the race," Democratic strategist Jenny Backus said. "Obama is moving and gathering a bigger coalition, and Hillary's coalition is diminishing."

In the face of so many losses, the Clinton campaign has tried gamely to recalibrate expectations -- signaling loudly that February would not be a good month for the New York senator. Her strategists even are discounting the power of Obama's momentum and are instead framing the contest as a drawn-out hunt for delegates that might not conclude until the party's national convention in Denver this August.

But to do so is to ignore all the other measures of campaign success -- all of which now favor Obama. His campaign has brought in more than $1 million per day from more than 650,000 contributors, allowing him to flood the primary states with television ads and staff. Clinton, meanwhile, is still climbing out of a financial hole that forced her to make a $5 million personal loan to the campaign.

Obama also continues to draw arena-sized crowds to his rallies, dwarfing Clinton's smaller but still enthusiastic gatherings.

In the face of such numbers, Clinton strategists have taken a risk -- all but pinning her candidacy to the outcome of primaries in Texas and Ohio on March 4. The two states are large and delegate-rich, and their demographics -- working-class white voters in Ohio, a large Hispanic population in Texas -- have so far favored her candidacy.

Clinton was traveling to Texas Tuesday while Obama was heading to Wisconsin, whose primary is Feb. 19.

To be sure, Clinton's strength among traditional Democratic constituencies has proven durable and has effectively prevented Obama from running away with the contest so far. And Clinton has rightly said that a Democrat would be hard pressed to win a general election without the support of the party's base.

But Obama has begun to make inroads in those voting blocs -- winning a caucus in Maine on Sunday that was dominated by white, working-class voters. He has prevailed with blacks, another cornerstone of the Democratic base, while creating a new alliance of voters not always associated with the party, including independents, affluent voters, young people and men.

Obama's major challenge is attracting working-class women -- loyal Democrats who form the base of Clinton's constituency.

Those voters and the economic anxiety they face are what could allow Clinton to remain viable, Backus said.

"The Clinton campaign can't have it be about states won or lost or delegates won," she said. "It needs to be about electability in the fall, strength against John McCain, and the key issues voters are facing."