A procedural vote Wednesday ended the U.S. Senate's consideration of an amendment to define marriage as only between a man and a woman.

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Republicans did not have enough votes to break a Democratic filibuster that would allow consideration of a change to the proposed amendment. The 50-48 vote was 12 short of the 60 needed to keep the measure alive.

Republicans proposed separate versions of the measure.

One version was just one sentence long, stating that marriage in the United States could only be between a woman and a man. A longer version clarified that no state's constitution "shall be construed to require that marriage or the legal incidence thereof be conferred upon any union other than the union of a man and a woman."

Democrats successfully bet that the Senate would not reach the 60 votes needed to break the deadlock. It means that senators did not vote specifically on the amendment, just on whether to continue debate.

But the amendment's sponsor, Colorado Republican Wayne Allard, said before the vote, "We're just beginning to defend marriage, and this debate may go well beyond this year."

Missouri Republican Jim Talent said Americans of all races and religions support traditional marriage and believe that children do best in a family with a mother and a father.

But California Democrat Barbara Boxer said some faiths recognize same-sex marriage, and she called the proposed amendment "a weapon of mass distraction" from more important issues.

Even if the amendment were to pass Congress, it would need to be ratified by the states before taking effect.

Senators John Kerry and John Edwards were the only two not to vote.

President George W. Bush called for the amendment earlier this year after a court ruling in Massachusetts said that state cannot prevent same-sex couples from marrying under its constitution. The state began allowing homosexual couples to marry this spring, though the state Legislature has already passed a preliminary amendment to end the practice.

That amendment must be approved by legislators again, and then by the people of the state.

House Looks At Marriage, Too

Meanwhile, the House Judiciary Committee holds a hearing Wednesday on a measure that would strip federal courts of jurisdiction over the federal Defense of Marriage Act.

The DOMA, as it's called, passed Congress overwhelmingly and was signed into law by President Bill Clinton in 1996. It defines marriage as the union of a man and a woman under federal law and exempts states from being forced to recognize gay marriages performed in other states.

Some senators argue that DOMA precludes the need for a constitutional ban on gay marriage. But supporters of the Federal Marriage Amendment say federal courts could soon strike down the 1996 law.

Article III, Section 2 of the U.S. Constitution gives Congress the power to remove issues from federal courts' jurisdiction. Unlike a constitutional amendment, such a bill would only need a majority of the House and Senate and the president's signature to take effect.