Updated at 4:15 p.m. ET.
The Senate voted on Thursday on the first two amendments offered to Democrats' health care reform package, deciding to ensure mammogram insurance coverage in the new health care system, and rejecting an attempt to strip Medicare cuts out of the bill.
In its first vote, the Senate narrowly approved an amendment to safeguard coverage of mammograms and preventive screening tests for women under a revamped system.
The 61-39 vote on an amendment by Sen. Barbara Mikulski, D-Md., and Sen. Olympia Snowe, R-Maine, would allow the Health and Human Services secretary to require insurers to cover preventive health screenings free of charge.
Under special provisions agreed to prior to the tally, 60 votes were needed to pass the amendment. The margin underscored the fragility of the coalition Democrats are counting on to move forward on President Barack Obama's signature issue.
Though Democrats have 60 votes in the Senate, two Democratic senators voted against the amendment - Sen. Russell Feingold of Wisconsin and Ben Nelson of Nebraska. It was saved by three Republicans voting in favor - Snowe, Susan Collins of Maine and David Vitter of Louisiana.
The Senate also voted 42 to 58 to reject Republican Sen. John McCain's amendment to strip more than $400 billion in Medicare cuts from the bill. Democratic Sens. Ben Nelson and Jim Webb voted with Republicans in favor of the amendment. The measure would have sent the bill back to the Senate Finance Committee for a redo.
Republicans said the cuts to health insurance plans and medical providers would mean seniors in the popular Medicare Advantage program will lose some benefits. Democrats said no guaranteed benefits will be lost, and the cuts will help keep Medicare solvent. AARP threw its support to the Democrats.
Waiting in the wings is an amendment to restrict abortion funding, except in cases of rape, incest, or to save the life of the mother. Drafted by Nelson, an abortion opponent, it looms as perhaps the biggest challenge for the Democrats.
The mammogram coverage vote comes in the wake of heated controversy over a government advisory panel's recent recommendation that routine mammograms aren't needed for women in their 40s. Although the advisers' recommendation was nonbinding, it prompted fears that the health care legislation would usher in an era of rationing.
The Mikulski-Snowe amendment would give the health and human services secretary authority to require health plans to cover additional preventive services for women. The Congressional Budget Office said the amendment would cost $940 million over a decade.
Mikulski said her amendment would guarantee that decisions are left to women and their doctors, not placed in the hands of government bureaucrats or medical statisticians. She accepted a modification to her amendment by Vitter that would specifically prevent the controversial recommendations on mammograms from restricting coverage of the test.
However, Republicans said that Mikulski's amendment still left too much discretion to the HHS secretary. A competing amendment by Sen. Lisa Murkowski, R-Alaska, would prevent the government from using the recommendations of outside advisers to deny coverage of preventive services, including mammograms and Pap tests.