WASHINGTON — Confronting a string of primary defeats, Sen. Hillary Rodham Clinton's presidential campaign scurried to reassure anxious donors Wednesday, and the candidate struck a more combative tone to ramp up pressure on Sen. Barack Obama heading into the next contests.
Clinton held a morning conference call with top donors, one day after she lost Democratic primaries in Maryland, Virginia and Washington, D.C. Her message, according to a person who took part in the call: The results were neither unexpected nor fatal, and the campaign will regroup on March 4 with victories in the delegate-heavy states of Texas and Ohio.
One campaign aide, speaking privately, said that a defeat in Texas or Ohio might be more than Clinton could withstand.
But Mark Penn, a Clinton pollster and top strategist, said it won't come to that. "From our perspective, we expect change to begin March 4," he said.
Should Clinton lose Tuesday in Hawaii and Wisconsin -- and aides concede that could happen -- she will have been beaten in 10 straight contests.
Her supporters are watching the streak with mounting unease.
"No one believed we would win every primary, but I don't think there are too many Clinton supporters who thought we would lose [so many] in a row," said U.S. Rep. Anthony Weiner (D-N.Y.), who has traveled with the Clinton campaign.
Garry Shay, a Los Angeles attorney, is both a Clinton backer and a superdelegate to the Democratic convention. If neither Clinton nor Obama comes out of the primary season with a clear victory, Shay and nearly 800 other superdelegates could be in a position to pick the winner.
Shay said Wednesday that he might rethink his support if Obama enters the convention having racked up more delegates in state-by-state races.
"It's fair to say I'm concerned about it," he said. "Clearly, you can't go on losing primaries and think you're going to win the nomination."
Hoping to put Obama on the defensive, the Clinton campaign began airing an ad in Wisconsin that chides him for refusing to take part in a televised debate there. Clinton's campaign believes she outperforms Obama in these forums and is eager to schedule as many one-on-one debates as possible.
The 30-second spot is one of the most pointed Clinton has aired to date, though her campaign described it as "straightforward." It says of Obama: "Maybe he'd prefer to give speeches than have to answer questions."
Obama has agreed to debate her twice over the next two weeks: in Austin, Texas, on Feb. 21 and in Cleveland five days later. Obama spokesman Bill Burton said Obama was not ducking debates, noting that the two candidates will have taken part in 20 Democratic debates by month's end.
Amid the setbacks, Clinton aides are considering whether to retool her message. They discussed it Tuesday night in a conference call as the polls were closing. One person who took part in the call said there was talk about softening her image and sharpening the charge that Obama offers rhetoric while she provides substance.
"It would be folly for us not to reevaluate, retool and readjust whenever appropriate," said Los Angeles Mayor Antonio Villaraigosa, a Clinton campaign surrogate.
It is plausible that neither Obama nor Clinton will clinch the nomination the traditional way -- winning a sufficient number of delegates through primaries and caucuses. A total of 2,025 delegates are needed to get the nomination.
Clinton is scratching for each one. Aides said she was opening a campaign office in Puerto Rico, which holds a caucus June 7. At stake: 63 delegates.
Both candidates are battling not just on the campaign trail but in the realm of public opinion. Each offers a different picture of what victory would look like.
Obama's top strategists said Wednesday that they would emphasize the so-called pledged delegates who are elected to the national nominating convention by voters in primaries and caucuses.
Campaign manager David Plouffe predicted that whoever wins the most of those delegates will win the nomination -- and he said it would be "next to impossible" for Clinton to overcome Obama's lead in that category.
"The only way for her to erode that is to win contests in blowouts," Plouffe said. "And we see no evidence in any of the remaining contests where that would be possible."
Clinton may be coming up with a different definition of victory. Some of her aides and supporters say she will have earned the nomination by performing well in big states that are crucial to a Democratic victory in the fall. She already has won California, New York and New Jersey -- and is polling ahead of Obama in Texas, Ohio and Pennsylvania.
A top Clinton fundraiser wondered how Obama could lay claim to the Democratic nomination having lost those states. "I don't see how anyone losing those states could make a credible claim that they are going to get the nomination or that they deserve the nomination," said Richard Schiffrin, a regional campaign finance chairman.