The bill authorizing 2004 defense programs now goes to President Bush for his signature.
Most Democrats joined Republicans in the 95-3 vote, despite objecting to the broader Pentagon authority. But the bill was opposed by Sen. Robert C. Byrd (D-W.Va.), who said it "transfers vast, unchecked powers to the Defense Department while avoiding any break with the business-as-usual approach to increasing defense spending."
In addition to Byrd, Sens. Daniel K. Akaka (D-Hawaii) and James M. Jeffords (I-Vt.) voted against the bill. Two Democrats, both presidential candidates, were absent: John F. Kerry of Massachusetts and John Edwards of North Carolina.
The bill was $1.5 billion more than the amount requested by Bush and about 2.2% more than Congress approved last year. It was approved by the House on Friday in a 362-40 vote.
It would raise soldiers' salaries by an average of 4.15% and extend increases in combat and family-separation pay.
It also would partially reverse an 1890s policy of reducing disabled veterans' retirement benefits by $1 for every dollar received in disability pay.
In a compromise, the bill would allow the Air Force to lease 20 Boeing 767 planes as midair refueling tankers and buy an additional 80.
The Pentagon lobbied most intensively over changes that would affect civil service and environmental regulations -- and generally prevailed.
Under the bill, it would have greater flexibility in hiring, firing and promoting civilian employees. Democrats and unions say it would hurt workers by weakening job protections, overtime rules and other rights.