After news broke that Mrs. Clinton had lent her campaign $5 million following the crush of states that voted on Feb. 5, the campaign brought in more than $4 million in 24 hours; and after Mrs. Clinton’s popular-vote victories in Ohio and Texas on March 4, the campaign collected more than $3 million. The Obama campaign often averaged more than $1 million a day online earlier in the year.

Image Senator Hillary Rodham Clinton at a rally on Thursday in West Virginia, one of six remaining states with primary contests. Credit... Stephen Crowley/The New York Times

Nevertheless, Mr. Nemazee said that $1 million at this point in the race was an impressive total for Mrs. Clinton to have raised. “We raised a million dollars in a 24-hour period for a candidate that every pundit is saying is either toast or dead on arrival,” he said. “People at the grass roots are still willing to spend $5, $25, $50, whatever it is, to be supportive.”

Mr. Nemazee also said that the fund-raiser in Washington on Wednesday, which had been expected to bring in $500,000, had actually raised more than $1 million. He added that a Mother’s Day-theme event on Saturday in New York with Mrs. Clinton and her daughter, Chelsea, was on track to bring in more than $200,000.

“That is not indicative to me of a lack of support,” Mr. Nemazee said. “We’re in the 16th month of the campaign for a candidate that everyone says has no path to victory.”

Still, other top fund-raisers working for Mrs. Clinton said that enthusiasm among donors had fallen sharply and that they had little confidence there would be a financial turnaround. They said that some donors had questioned why they should give more money when another set of numbers  the calculus to win enough delegates for the nomination  seemed so against Mrs. Clinton at this point.

At the end of March, the most recent period for which figures are available, Mrs. Clinton had $9 million available for her primary bid, compared with $43 million raised in primary money for Mr. Obama. Mr. Obama also had less than $1 million in debt.