Supporters said Wednesday the Senate Armed Services Committee has enough votes to approve a bill overturning the ban on gays serving openly in the military.
The prediction came after several lawmakers on the panel signaled their support, including Sen. Ben Nelson, a conservative Democrat from Nebraska who had been considered a holdout.
"In a military which values honesty and integrity, this policy encourages deceit," Nelson said of the 17-year-old "don't ask, don't tell" law.
The bill would still face scrutiny by the full Senate, where 60 votes are usually needed to overcome Republican objections.
But an endorsement by the Senate Armed Services Committee, led by Michigan Democrat Carl Levin, was considered a crucial first step by gay rights' groups.
The measure is more likely to survive because it was being tucked into a broader defense policy bill that typically includes popular provisions like a pay raise for the troops.
The committee planned to vote on Thursday.
"We are increasingly confident about the (bill) and that this could very well be a historic week in the United States Congress," said Marshall Wittmann, a spokesman for Sen. Joseph Lieberman, I-Conn., who is co-sponsoring the legislation.
Gay rights groups were cautiously optimistic.
"This one will go down to the wire, and it won't be over until the vote," said Fred Sainz, a spokesman for Human Rights Campaign.
The legislation was a compromise between the White House and a small group of Democrats — including Levin and Lieberman — who fear that repeal efforts will be doomed if Republicans regain control of one or both houses of Congress after fall elections.
The plan would overturn the "don't ask, don't tell" law but still allow the military to decide when and how to implement any changes to accommodate the new policy.
Nelson said this caveat was key to his support because it "removes politics from the process" and ensures repeal is "consistent with military readiness and effectiveness."
Defense Secretary Robert Gates said he supports repeal but would prefer that Congress wait to vote until he can talk to the troops and chart a path forward. A study ordered by Gates is due on Dec. 1.
Some lawmakers, including Democrats, took a similar stand this week and cast doubt that the measure might pass.
"I see no reason for the political process to pre-empt it," Sen. Jim Webb, a conservative Democrat from Virginia, said of the military study.
At least one Republican — Sen. Susan Collins of Maine — has said she will support the measure.
The House planned to consider an identical bill on Thursday. Rep. Patrick Murphy, D-Pa., was expected to introduce the legislation as a floor amendment to the 2011 defense authorization bill.
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