COLUMBIA, S.C. - A House bill that would let voters decide next year whether the state Constitution should be changed to bar same-sex unions headed to the Senate Judiciary Committee on Thursday.

Two senators on opposite sides of the legislation told a crowd of nearly 100 opponents that they need to face the reality that the issue will be on the ballot in November 2006 and devote themselves to fighting the amendment then.

The amendment says marriage is "exclusively defined as a union between one man and one woman" and all other unions are void. State law already says that, but supporters say a judge could strike that down and open the door to gay unions here.

Clemson economist Holley Ulbrich told the panel that during a more than four hour public hearing that the state will lose money, talent and opportunity if it gains the reputation of being less tolerant. A study showed a 1993 policies toward gays Cincinnati adopted in 1993 cost that city $46 million in convention business alone, Ulbrich said.

"Passing the amendment has an effect on how South Carolina is perceived," Ulbrich says.

Opponents said gay marriages upend tradition and undermine heterosexual unions.

"Marriage is always heterosexual" and is a way of protecting women from exploitive males, containing male sexuality and aggression and giving children the best opportunity to thrive, said Oran Smith, president of the Palmetto Family Council. "There is no public need for a same-sex family," Smith said.

Sen. Jake Knotts, R-West Columbia, sat through hearing and told the crowd nothing had changed his mind on the bill. "You've got a lot of work to do. This bill is going to be passed. It is going to be put on the ballot," Knotts said.

In the months ahead, he told gay advocates that they have a lot of educating to do to change public opinion. "You're going to have to win the battle. That's just the way that it is. Sorry," Knotts said.

Sen. Robert Ford, D-Charleston, at one point had spoken of multiple public hearings that could have kept the issue tied up for months. But on Thursday, he conceded that wasn't going to happen.

Even the issue of a vote on the bill had been taken out of his hands in the subcommittee he chaired because no matter what he did, the legislation would have been on the Judiciary Committee's agenda for a specially called meeting Tuesday.

Knotts, Ford said, was describing the political reality. "You've got a lot of work to do. .... You've got to stop being afraid. I know it's hard, but you've got to stop being afraid," he said.