His announcement makes good on his pre-election promise to resurrect during the lame-duck session legislation that would repeal the 1993 law known as "don't ask, don't tell."
"We need to repeal this discriminatory policy so that any American who wants to defend our country can do so," Reid said in a statement.
The legislation would allow for the first time gay troops to acknowledge publicly their sexual orientation. However, the repeal of the current law would take effect after the president and his top military advisers certify that doing so would not hurt the military's ability to fight.
The bill was considered a deal struck earlier this year between more liberal Democrats eager to change the law and the White House, under pressure by the Pentagon to give it more time to determine how to repeal the law without causing any backlash.
The provision is tucked into a broader defense policy bill that includes such popular programs as a pay raise for the troops, which gay rights groups hoped would help its chances of passing.
But when the bill reached the floor in September — just weeks before the midterm elections — Republicans united in objecting to its debate on procedural grounds. Reid insisted that few amendments be considered in the interest of time; Republicans said restricting debate on such a wide-ranging policy bill was unfair.
Jim Manley, a spokesman for Reid, said Wednesday that it had not been decided yet how many or which amendments might be considered for debate.
A wild card in the upcoming debate will be a Pentagon study on gays in the military that is likely to be released just days before the Senate vote. Last February, Defense Secretary Robert Gates said he supports an eventual repeal of the law but wanted time to figure out how it should be done. He ordered a 10-month study due Dec. 1.
A draft of the 370-page assessment has found that the ban could be lifted with little harm and that most troops don't object to the change in personnel policy, according to officials familiar with its findings. But it also found that some troops had serious concerns with repealing the law.
Military officials have warned that even scattered resistance to the change could pose logistical and discipline problems for field commanders.
Sen. Carl Levin, who has been leading the repeal push in the Senate, said he had asked Reid for a vote after the Pentagon study is released and he has a chance to hold hearings on the issue in the first few days of December. Levin, D-Mich., chairs the Senate Armed Services Committee.
A spokeswoman for McCain, R-Ariz., did not immediately respond to requests for comment.
Gay rights groups see the lame-duck session as their best chance at repealing the law. The House has already passed the bill. But come January when the new Congress is seated, Republicans will take control the House and the Democratic majority in the Senate will be narrowed by six seats.
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