OLYMPIA — An attempt to ban discrimination against gays and lesbians suffered a serious setback yesterday when state Senate Republicans used a procedural move to send the bill to a committee where opponents appear to have the votes to defeat it.

Democrats hold a narrow majority in the Senate, but Republicans enlisted the aid of two conservative Democrats to send House Bill 1515 to the Senate Judiciary Committee.

Democratic Sens. Jim Hargrove of Hoquiam and Tim Sheldon of Potlatch, Mason County, sided with the GOP in the 25-24 vote. Hargrove also sits on the Judiciary Committee and said he would side with Republicans there as well, giving the GOP the votes to prevent the bill from returning to the Senate floor.

State law already bans discrimination by race, sex, religion, national origin, marital status and other categories. The bill would add sexual orientation to that list.

The measure has been around in some form for at least 25 years. It passed the House in February by its largest margin ever, including several Republican votes. Senate Majority Leader Lisa Brown, D-Spokane, and other Democrats say they expect the measure to pass the Senate if they can get it to the floor for a vote.

"We won't give up on it," Brown said, visibly angered by yesterday's vote.

Rep. Ed Murray, D-Seattle, the bill's prime sponsor in the House, agreed as he rushed to a meeting to discuss ways to save the legislation. "It's not over until it's over."

Senate Republicans yesterday argued they were simply moving the bill, which had earlier passed the Senate Financial Institutions, Housing and Consumer Protection Committee, to the proper committee for consideration.

It's just about "what's the right committee," said Senate Republican floor leader Luke Esser, R-Bellevue. "Everybody has always agreed the Judiciary Committee is the proper committee."

Esser said he was concerned that if the bill passed, it might open the door for gay marriage. "I don't want to do anything to put us on a slippery slope," he said.

The Senate Republican caucus yesterday handed out a five-page "talking points" document opposing the measure. One of the talking points states: "This bill establishes minority status for individuals based on sexual behaviors many believe they choose to engage in."

Republican Minority Leader Bill Finkbeiner, R-Kirkland, declined comment yesterday.

Brown said it was time for the Legislature to signal that it was getting the government out of people's bedrooms, "that what matters at work is that you're a good employee, that what matters when you go to the bank is that you don't bounce checks."

Hargrove said it's not just a moral question for him, but also that he had given his word to people that he would vote against it. "You try to make as few commitments as possible, but this is one I've made."

Sheldon said he sided with Republicans because he comes from a conservative district where most people oppose the measure. By preventing a floor vote on the bill, "I'm representing their wishes," he said.

Brown would not discuss what the options are for reviving the bill.

Sen. Darlene Fairley, D-Lake Forest Park, an ardent supporter of the measure, said possibilities include getting a few moderate Republicans to side with Democrats and pull it back to the floor for a vote. Senate Democrats also could "amend portions of it onto other bills," she said. "There are other ways to get it."

Still, Fairley said the Republican move hurts efforts to get the legislation passed this session.

"It's a big setback. The bill was on a regular track just like any other bill. Instead of allowing it to work like any other bill, they make it a special target of attack," she said.

"It's like it was the most important bill to them of all. They don't do this with budget bills or tax bills."

Times staff reporter Ralph Thomas contributed to this report. Andrew Garber: 360-943-9882 or agarber@seattletimes.com