In October, a University of Washington poll found that an increasing number of people support same-sex marriage. About 43 percent of respondents said they support gay marriage, up from 30 percent in the same poll five years earlier. Another 22 percent said they support giving identical rights to gay couples but just not calling it marriage.
When asked how they would vote if a referendum challenging a gay marriage law was on the ballot, 55 percent said they would vote yes to uphold the law, with 47 percent of them characterized as "strongly" yes, and 38 percent responded "no," that they would vote to reject a gay marriage law.
If a marriage bill were passed, gay and lesbian couples would be able to get married starting in June unless opponents file a referendum to challenge it at the ballot.
Under the bills being considered by the Legislature, people currently registered in domestic partnerships would have two years to either dissolve their relationship or get married. Domestic partnerships that aren't ended prior to June 30, 2014, would automatically become marriages.
Domestic partnerships would remain for senior couples where at least one partner is 62 years old or older. That provision was included by lawmakers in 2007 to help seniors who don't remarry out of fear they could lose certain pension or Social Security benefits.
The measure doesn't require religious organizations or churches to perform marriages, and doesn't subject them to penalties if they don't marry gay or lesbian couples.
But several religious groups have opposed any discussion of gay marriage. This month, the Catholic bishops of Washington issued a statement saying that same-sex marriage was not in the public interest and calling on "the citizens of this state to maintain the legal definition of marriage."
Joseph Backholm, executive director of The Family Policy Institute of Washington, said that the debate "really does go to the core of who we are, and what matters in the big picture."
"What we're being offered is that marriage is for the purpose of validating relationships. If that is true, that is a shaky foundation and one that establishes precedent that no one wants to follow," he said.
Earlier this week, the National Organization for Marriage announced that it would spend $250,000 to help fund primary challenges to any Republican who crosses party lines to vote for same-sex marriage in Washington state. So far, two Republicans in the Senate, and two in the House have said they would vote in support of gay marriage.
Rep. Jamie Pedersen, a Democrat from Seattle who is sponsor of the House bill, said that even if a gay marriage law doesn't pass this year, the stage has been set for future success.
"This change is inevitable," he said. "It's just a question of how long the families of same-sex families are going to have to wait for that justice to be done."