The House passed on Wednesday a bill to end the ban against gays and lesbians serving openly in the military.
The 250-175 vote sends the "don't ask, don't tell" repeal to the Senate, which is expected to vote on it next week.
This is the third time this year that DADT repeal legislation has reached the Senate. Previously, the repeal was tacked onto a Defense Authorization bill. But after failing to get passed the Senate twice, the House moved to introduce a freestanding bill.
President Barack Obama and Defense Secretary Robert M. Gates are backing a quick repeal.
Doug Carlson of the Ethics & Religious Liberty Commission denounced the attempt to ram through a repeal of the 1993 policy in the lame-duck session.
"This Christmas, the upper chamber is hoping to deliver another unwanted present: repeal of two centuries of military conduct policy against open homosexuals in the military," he said. "To rush through repeal would be no welcomed Christmas present to our troops. It would be a grave disservice to our valiant servicemen and women."
Family Research Council President and Marine Corps veteran Tony Perkins has called out Congress for sacrificing U.S. troops to a political agenda.
"By making this change, and putting it as a priority over the actual funding of the troops, Congress is choosing to use the military, not as a tool for national defense, but as an instrument of social engineering," he said after the House vote.
Perkins rejected the House for ignoring the pleas of seasoned commanders, including Marine Corps Commandant Gen. James Amos.
A day ahead of the House vote, Amos said combat Marines are concerned that a DADT repeal may be a distraction.
"I don't want to lose any Marines to the distraction," he warned. "I don't want to have any Marines that I'm visiting at Bethesda [Naval Medical Center] with no legs be the result of any type of distraction.
"Right now is a very intense period of time for a pretty healthy slice of the United States Marine Corps. This is not training. This is what I call the real deal. And the forces that wear this uniform ... came back and told their commandant of the Marine Corps that they have concerns. That's all I need. I don't need a staff study. I don't need to hire three PhDs to tell me [how] to interpret it... [I]f they have concerns, I do too. It's as simple as that."
The stand-alone bill to repeal DADT was sponsored by Joseph I. Lieberman (I-Conn.) and Susan Collins (R-Maine).