The Republican-led US House of Representatives has approved a bill to curb same-sex marriage after rejecting concerns the measure may be unconstitutional.
On a vote of 233-194 on Thursday, the House sent the proposal to the Senate where members of both parties said it will likely die. But it could help focus attention on same-sex marriage as an election-year issue.
Last week, the Senate easily blocked a bid pushed by President George W. Bush to amend the Constitution to define marriage as a union strictly between a man and a woman.
New York Democrat Rep. Jerrold Nadler
The House measure, also supported by the administration, offers a different approach. It would forbid federal judges from requiring one state to recognise a same-sex marriage licensed in another.
Democrats accused Mr Bush and fellow Republicans of pushing the proposals merely to rally their conservative base for the November congressional and presidential contests.
"This debate is about a national election," Rep. Jerrold Nadler, a New York Democrat, said in opposing the bill. "We are playing with fire with this bill, and that fire could destroy the nation we love."
Democrats called the bill unprecedented, but backers said Congress had moved before to limit courts' authority on matters from cleaning up hazardous waste to protecting trees.
"If limiting the jurisdiction of the federal courts is good enough to protect trees, shouldn't it be good enough to protect a state's marriage policy?" House Judiciary Committee Chairman James Sensenbrenner, a Wisconsin Republican, said.
The House bill would prohibit federal courts, even the Supreme Court, from considering challenges to the 1996 US defence of Marriage Act, which empowered each state to decide on its own whether to allow same-sex marriage.
Opponents contend the bill would violate the equal protection clause by cutting off from federal judicial review a law affecting a specific minority.
Polls show most Americans oppose same-sex marriage, but split on whether there should be a constitutional amendment to ban it. Surveys also find Americans believe several other issues are far more important, such as health care and the economy.