Senate Republicans may be short on votes to advance a proposed constitutional amendment to ban same-sex marriage today, but members of Utah's congressional delegation say such a measure is essential to protect traditional marriage from what they call activist judges.

The Federal Marriage Amend- ment would define marriage as "the union of a man and a woman."

"We clearly don't have enough votes," Sen. Orrin Hatch, R-Utah, said of the measure, which needs 60 votes to move beyond today's test vote. "Like most very important issues, you have to start somewhere."

Republicans, who said this won't be the end of the debate, held out hope they could gain a majority. Even that seemed in doubt, although their chances improved when an aide to Sen. John Kerry said he and vice presidential running mate John Edwards did not intend to return to the Capitol for what amounted to a procedural vote. Both men oppose the amendment.

A second part to the amendment states that neither federal nor state constitutions "shall be construed to require marriage or the legal incidents thereof be conferred upon any union other than the union of a man and a woman."

Some critics argue that the effect of that provision would be to ban civil unions, and its inclusion in the amendment has complicated efforts by GOP leaders to gain support from wavering Republicans.

Hatch, however, said the issue of civil unions should be left to the states to decide. He said he supports civil rights for gays and lesbians, but maintains there are ways to address those issues without "undermining marriage."

Democrats, many of whom oppose the measure, took delight in the internal Republican woes, and Sen. Dick Durbin of Illinois read aloud from a recent statement on the issue by Lynne Cheney, wife of the vice president. "When it comes to conferring legal status on relationships, that is a matter that should be left to the states," he quoted her as saying.

Hatch and others in Utah's delegation, however, said the measure is necessary to protect marriage laws in states such as Utah, in light of the Massachusetts Supreme Court decision that legalized same-sex unions in that state.

Hatch told the Deseret Morning News that a constitutional amendment, which requires a two-thirds majority in both houses of Congress before moving to the states, is the only way to give states a say on the issue.

"It takes three-fourths of the states to ratify an amendment," Hatch said. "States will have a say on the issue. It's the only way states will have a say."

Speaking to the Senate on Tuesday, Hatch called such decisions "an unprecedented usurpation of the people's will," noting that most states, including Utah, have defense of marriage laws or similar legislation.