SACRAMENTO (AP) – An effort to legalize same-sex marriage in California failed when supporters could not find the votes to make the state Assembly the first legislative chamber in the nation to give same-sex couples the same rights as heterosexuals.

The 37-36 vote Thursday marked the second time in two days the bill failed to gain the simple majority it needed to pass the 80-member house.

The bill’s author, Assemblyman Mark Leno, one of six openly gay members of the Legislature, said he was “enormously disappointed, frustrated, confused and exasperated.”

“If this body can’t pass [this bill] it should clarify its position and say we do believe gay and lesbian couples are in fact not first-class citizens,” said Leno, D-San Francisco. “That is the statement that was made tonight.”

Nearly a quarter of the majority Democrats either joined Republicans in opposing the bill or chose not to take a stand on the hot-button topic, now headed for likely showdowns in the state’s courts and at the ballot box.

“Voting for this bill may erode the advances we have made,” said Gloria Negrete McLeod, a Chino Democrat who abstained despite having a pro gay rights record. “It’s a shame we get into these things where we become so politicized and polarized.”

While it took a court order for Massachusetts last year to become the first state to grant marriage rights to same-sex couples, gay rights advocates had looked to California to be the first Legislature to do so voluntarily.

The bill would have amended the state family code to define marriage between “two persons” instead of between a man and a woman.

Although supporters never expected it would be easy to get the measure through the Assembly, they were cautiously optimistic about its chances given the state’s strong domestic partnership laws. The effort was buoyed in March when a trial judge in San Francisco ruled that state laws prohibiting same-sex marriage are unconstitutional.

Assembly Speaker Fabian Nunez had pledged to make it a priority to get Democrats, who hold 48 of the 80 seats in the house, to send the same-sex marriage bill to Gov. Arnold Schwarzenegger.

On June 2, Davis residents Ellen Pontac and Shelly Bailes anxiously roamed the hallways of the Capitol to appeal to uncommitted lawmakers to grant legal recognition to their relationship of 31 years.

“When the vote came down I felt like I was being kicked in the stomach,” Bailes said. “But now I’ve picked myself up and I’m ready to fight again.”

The bill’s Republican opponents argued that legislators had no business making same-sex marriage legal when California voters approved a ballot initiative five years ago prohibiting the state from recognizing same-sex marriages.

That argument proved persuasive with some Democrats as well. Assemblymember Nicole Parra, D-Bakersfield, said that even if she didn’t personally oppose making marriage available to same-sex couples, she wouldn’t have voted for the bill because she represents an area that strongly supported the ballot measure.

Lawsuits challenging the constitutionality of the state’s marriage laws are likely to wind up before the state Supreme Court within the next year. Opponents of same-sex marriage also have begun the process to put a constitutional amendment before voters that would ban same-sex nuptials and strip gay and lesbian couples of domestic partnership benefits. They hope to get the initiative on the June 2006 ballot.

If the bill had passed, it was expected to gain more support in the Senate, where Democrats hold a 25-15 advantage.

Leno said he would keep his options open to get the bill passed this year. One possibility includes adding the language to a Senate bill. If that fails, he also pledged to reintroduce the measure next year.

Even if it had cleared the Legislature, the bill’s ultimate fate was uncertain because Schwarzenegger, a moderate Republican, had not taken a stand on it. He has said voters or judges, not lawmakers, should make such social changes.

Supporters expressed disappointment with last week’s outcome but said the floor vote nonetheless represented a historic event for the gay rights movement.

“We had people who were adamantly against it last year who were speaking adamantly in favor of it on the floor,” said Assemblymember Sally Lieber, D-Santa Clara. “This was progress even though it’s not enough.”

Not Voting: 7

AYES: Bass, Berg, Bermudez, Calderon, Canciamilla, Chan, Chavez, Chu, Cohn, Coto, De La Torre, Evans, Frommer, Goldberg, Hancock, Jones, Karnette, Klehs, Koretz, Laird, Leno, Levine, Lieber, Liu, Montanez, Mullin, Nation, Nava, Oropeza, Pavley, Ridley-Thomas, Ruskin, Saldaña, Torrico, Wolk, Yee and Nunez

NOES: Aghazarian, Arambula, Baca, Benoit, Blakeslee, Bogh, Cogdill, Daucher, De Vore, Emmerson, Garcia, Harman, Haynes, Shirley Horton, Houston, Huff, Keene, La Malfa, La Suer, Leslie, Matthews, Maze, McCarthy, Mountjoy, Nakanishi, Niello, Parra, Plescia, Sharon Runner, Spitzer, Strickland, Tran, Vargas, Villines, Walters and Wyland

ABSENT, ABSTAINING OR NOT VOTING: Dymally, Gordon, Jerome Horton, Negrete McLeod, Richman, Salinas and Umberg