OLYMPIA, Wash. — The Washington state legislature appears to have the votes necessary to legalize same-sex marriage, as another state Senator on Monday announced her support for the measure, giving proponents the 25 votes needed for passage.

State Sen. Mary Margaret Haugen (D-Camano Island), said Monday she would become the 25th Senator the support the bill, while hundreds of people filled the capitol to advocate for and against gay marriage.

The Senate began considering the bill during a morning committee hearing.

“I know this announcement makes me the so-called 25th vote, the vote that ensures passage. That’s neither here nor there. If I were the first or the seventh or the 28th vote, my position would not be any different,” Haugen said in a statement. “I happen to be the 25th because I insisted on taking this much time to hear from my constituents and to sort it out for myself, to reconcile my religious beliefs with my beliefs as an American, as a legislator, and as a wife and mother who cannot deny to others the joys and benefits I enjoy,” she added. Seattle Times

The state House already has enough lawmakers in support of the measure to approve it, and earlier this month Gov. Chris Gregoire announced her support for bill as well, calling it “the right thing to do.”

If a marriage bill is passed during this legislative session, gay and lesbian couples will be able to get married starting in June unless opponents file a referendum to challenge it.

Opponents, including the National Organization for Marriage (NOM) pledged its support to help mount a referendum campaign.

Last week, the NOM announced it would spend $250,000 in Washington state to help defeat any Republican who supports the bill. To date, two Republicans in the Senate and two in the House have said they would vote in support of gay marriage.

Same-sex marriage is already legal in six states — New York, Connecticut, Iowa, Massachusetts, New Hampshire and Vermont — and the District of Columbia.