Concerned that it could lose several primaries and caucuses through the rest of February, Senator Hillary Rodham Clinton’s campaign sought to create an alternate storyline of success on Thursday by announcing that Mrs. Clinton had raised $7.5 million online so far this month.

That unusually high figure was quickly overshadowed by Senator Barack Obama’s announcement that he had raised the same amount in 36 hours since the 22-state contest on Tuesday, in addition to the $32 million that he raised in January.

Mrs. Clinton drew $13.5 million in January.

With Tuesday behind them, the rivals have turned some of their ferocity away from voters and toward their donors, seeking the clear-cut victory in fund-raising that neither could secure at the ballot box this week, when Mr. Obama won 13 states and Mrs. Clinton 9.

Mr. Obama’s fund-raising dominance, especially his announcement on Jan. 31 that he had raised $32 million, has sent jitters through Mrs. Clinton’s donor base. Some of her biggest donors grew even more concerned on Wednesday when her advisers said that she had lent the campaign $5 million of her own money and that some senior aides were working this month without salaries.