A Senate committee yesterday sent the nomination of Lester M. Crawford as Food and Drug Administration commissioner to the floor by a voice vote, but Chairman Mike Enzi (R-Wyo.) said that he faces serious opposition and may not be approved.

After noting that senators from both parties have indicated they intend to place holds on Crawford's nomination over the agency's failure to rule on several controversial reproductive-health issues, Enzi urged colleagues to keep politics out of the confirmation process.

"Otherwise," he said, "I don't think it's possible for us to confirm any nominee to this position."

"We've got some people who want some things approved, and I've got some other people who don't want it approved," Enzi continued. "I've got others who want some other things undone. . . . I think we would set a dangerous precedent if any of us were to hold up the president's choice for FDA commissioner over one or two drugs."

Crawford's nomination has become entangled in two emotional political debates -- over the government's role regarding abortion, contraception and sexual activity, and whether the Bush administration has allowed conservative ideology to trump science.

During the hearing, Sens. Patty Murray (D-Wash.) and Hillary Rodham Clinton (D-N.Y.) said they will place a Senate floor hold on Crawford's nomination because the agency has not ruled on a long-standing application to make the emergency contraceptive Plan B more easily available. Crawford has been acting commissioner.

Murray said Crawford had told her that all the scientific issues involving the safety and effectiveness of Plan B were resolved months ago. "What other conclusion can I draw than the agency's decision-making process has been compromised?" she asked.

Some social conservatives oppose the Plan B application, arguing that it could encourage sexual promiscuity and that it at times represents abortion -- a position the medical community overwhelmingly rejects.

Although Republicans on the committee did not express concerns about Crawford yesterday, others in the Senate have been critical. Sen. Tom Coburn (R-Okla.) has said he will place a hold on the nomination until the agency issues congressionally mandated new labeling for condom packages that outlines limits on their effectiveness.

Sen. Sam Brownback (R-Kan.) has voiced concern about the FDA's oversight of the abortion pill, RU-486. A citizen's petition asking the agency to take it off the market for safety reasons was filed in 2002, and opponents of abortion have been frustrated by the lack of a response.

Yesterday's support of Crawford by the Senate Health, Education, Labor, and Pensions Committee came during a voice vote, with Clinton, Murray and Sen. Barbara A. Mikulski (D-Md.) clearly dissenting.

Sen. Edward M. Kennedy (Mass.), the committee's ranking Democrat, said he shares his colleagues' concerns over the FDA's handling of the Plan B issue but supports Crawford as qualified. He and Enzi said the FDA has been weakened by not having a permanent commissioner for more than a year and for almost three of the past four years.

Enzi and Kennedy said it is too early to know whether Crawford's nomination will survive the Senate holds, which take 60 votes to override.

Crawford's nomination was delayed for two months while the Department of Health and Human Services inspector general's office investigated charges that he had improperly given promotions to a woman in his office with whom he was personally involved. The inspector general reported last week that there was no evidence of a romantic affair between the two, but that "discrepancies" were found between Crawford's statements about how much he helped the woman win a coveted Senior Executive Service position and two others' statements.

The ranking Democrat on the FDA's appropriations subcommittee, Rep. Rosa L. DeLauro (Conn.), said yesterday that recent information received from the FDA has raised "serious concerns about Dr. Crawford's actions as acting head of FDA. These concerns must be addressed before he is given this important position permanently."

The Bush administration directed Crawford to avoid a subcommittee budget hearing in April. That absence led the committee to withhold 5 percent of the budget for the agency leadership.

Senators from both parties have said they might place holds on Lester M. Crawford's nomination.