(Honolulu, Hawaii) Hawaii, the state that adopted the nation’s first “defense of marriage” constitutional amendment a decade ago, has now become the latest battleground in the fight for same-sex civil unions.

It would become the fifth state to legalize the so-called alternative to gay marriage if the Democrat-dominated Legislature and Republican governor approve a civil union law. The measure was passed by the state House this month but it now faces the Senate, where a divided committee is to vote Tuesday.

Republican Gov. Linda Lingle has declined to comment on the issue and it’s unclear whether she would veto the bill.

Gay rights organizations argue that civil unions would promote basic equality in the nation’s most ethnically diverse state, but opponents fear the erosion of an island culture that values conventional family ties.

“Society in general is becoming more accepting,” said Suzanne King, a real estate office manager who is raising her 9-year-old daughter, Shylar Young, with her partner of nearly 28 years, Tambry Young. “It’s not unusual to come upon a gay family. There isn’t this fear that by giving us rights, it’s going to reduce the traditional family.”

King and Young said they want a civil union law so gay couples can more easily adopt children, share health benefits and gain hospital visitation rights. They plan to enter into a civil union if the measure becomes law.

Religious groups have been taking out newspaper ads, setting up Web sites and holding rallies urging lawmakers to preserve traditional marriage.

One anti-gay Web site includes photos of two men kissing each other and others apparently in gay pride parades. It warns of a bad influence on Hawaii “keiki,” the Hawaiian word for children.

The Mormon church, which campaigned in California last year for a gay marriage ban, has not openly rallied opposition to civil unions in Hawaii this year. But some members of the Church of Jesus Christ of Latter-day Saints have been sharing e-mails urging people to calls their legislators opposing the bill.

“In Hawaii, people still believe in traditional marriage and the sanctity of marriage,” said Dennis Arakaki, executive director of the Hawaii Family Forum, which also represents the Hawaii Catholic Conference. “There’s no indication that values or perspectives have changed.”

Several thousand people gathered at the state Capitol on Sunday for a demonstration organized by Arakaki’s group.

Protesters held signs saying “We affirm traditional marriage” and “No to same sex marriage” while listening to speakers in the Capitol’s open-air rotunda. Others signed petitions opposing the bill.

“We’re gathered here because we want our voices heard,” Wayne Cordeiro, senior pastor of New Hope Christian Fellowship in Honolulu, said to loud cheers from the crowd.

Rally volunteer Julia Sula said she came to the demonstration with 200 to 300 other members of her Waipahu church, the Lighthouse Outreach Center.

“We believe in traditional marriage: a woman to a man. Not `man to a man’ and `woman to a woman,’” said Sula, a 65-year-old retired social worker.

Only Massachusetts and Connecticut allow gay marriage, while Vermont, Connecticut, New Jersey and New Hampshire allow civil unions. Californians voted in November to overturn a court ruling that allowed gay marriage, but the state still offers domestic partnerships that guarantee the same rights as marriage.

That means Hawaii could become the only Western state to give governmental blessing to same-sex unions.

“Our wedding industry would have a huge potential increase in business purely because there are people who would rather come to the islands rather than go to the East Coast to have a civil union performed,” said the Rev. Mike John Hough of Kauai Island Weddings. “Some people say it’s just marriage by another name, and that may be true. It’s a perfect compromise.”

In 1998, nearly 70 percent of Hawaii voters approved a constitutional amendment granting the state Legislature the power to reserve marriage for opposite-sex couples. The “defense of marriage” amendment, now in more than half of state constitutions, resulted in a law banning gay marriage in Hawaii but left the door open for civil unions.

The amendment negated a 1993 Hawaii Supreme Court ruling that found refusing to grant marriage licenses to same-sex couples was discriminatory.

Since 1998, Hawaii’s Legislature has considered civil unions several times, most recently in 2007, but the bills never made it out of their committees.

This year, the House Judiciary Committee passed the measure by a 12-0 vote, and the full House approved it 33-17, one vote short of the two-thirds majority needed to override a potential veto.

Attitudes have changed, said state Rep. Blake Oshiro, who sponsored this year’s bill.

“People are more tolerant and accepting of diversity and recognizing the need for equality,” said Oshiro, a Democrat.