More than 2 million people have voluntarily enrolled for the new prescription drug benefit in the past month, exceeding projections by the Bush administration.

Health and Human Services Secretary Mike Leavitt touted the enrollment numbers on Monday as good news for a program that has stumbled in the early going. About 20 states have been compelled to help pay for medicine that many senior citizens and the disabled could not get through their new coverage.

"The program is working for the vast majority of participants quite well," Leavitt said. "We're filling more than a million prescriptions a day."

Sen. Hillary Rodham Clinton, D-N.Y., compared the government's effort to its response to Hurricane Katrina and called it "slow, inept and dangerous."

Leavitt acknowledged that the program was not working for some. He said the administration was working feverishly to address concerns that tens of thousands of people who can least afford to go without their medication are struggling.

He said he would begin a tour on Wednesday of numerous states — Oregon, California, Texas, Arkansas, Florida and Wisconsin among them — "to find out how things are working in the field."

The new drug benefit began on Jan. 1. About 42 million senior citizens and the disabled are eligible to enroll in private health plans that will subsidize their prescription drug costs.

Last month, the administration announced that about 21 million people would get drug coverage through the program.

About 1 million of that group had voluntarily enrolled. The rest were automatically enrolled because of their participation in other programs, such as Medicaid, or they would continue getting coverage through their employers, which are getting government subsidies to continue a prescription drug benefit.

Leavitt said he believes the additional 2 million enrollees over the past month is a signal that Medicare beneficiaries see value in the program.

Advocates for the elderly and disabled have raised concerns that some senior citizens are not showing up as being enrolled in plans and, in other instances, are being charged hundreds of dollars for medicine that should not cost more than $5.