With primaries on Tuesday in Maryland, Virginia, and the District of Columbia, Clinton advisers were pessimistic about her chances, though some held out hope for a surprise performance in Virginia.

And as polls show Mr. Obama gaining strength in Wisconsin and his native state, Hawaii, which vote next Tuesday, advisers, donors and superdelegates said they were resigned to a possible Obama sweep of the rest of February’s contests.

Some donors also expressed concern about a widening money imbalance between Mr. Obama and Mrs. Clinton: Obama fund-raisers say he is taking in roughly $1 million a day, while Clinton fund-raisers say she is taking in about half of that, mostly online. Mrs. Clinton’s aides say that the campaign was virtually broke as of the Feb. 5 primaries, but that finances have stabilized.

Mr. Obama’s financial edge allowed him to begin running television advertisements in Ohio and Texas on Monday, while the Clinton campaign plans to begin advertising on Tuesday. Clinton advisers say that she will have advertisements running statewide in both Ohio and Texas, and that she will have advertisements in English and Spanish in Texas.

“I think that clearly things have not been going as great as they were with her victories on Super Tuesday, and we can’t wait to get to March 4,” said Alan Patricof, one of Mrs. Clinton’s national finance chairmen.

Mrs. Clinton will have “a major ad buy” through the next week in Wisconsin, a senior adviser said Monday, and spend a few days campaigning there. But this adviser and others said the bulk of her time would be devoted to campaigning in Ohio, Texas and a bit in Rhode Island. In a sign of Texas’s importance, she plans to fly there Tuesday, even though Wisconsin votes next week.

While Mrs. Clinton’s advisers and allies emphasize that she has the time and the financial resources to regroup, they say she will have to take more significant steps to shore up her candidacy beyond the staff shakeup she engineered on Sunday, when she replaced her campaign manager and longtime aide, Patti Solis Doyle, with another veteran adviser, Maggie Williams.