Updated Thursday, November 8, 2012 at 04:46 PM
Opponents of same-sex marriage have conceded, saying it appears that Referendum 74 will pass.
Approval of the measure will make Washington the ninth state to allow gay marriage and the third to do so this week. Same-sex marriage is also legal in the District of Columbia.
"With added results showing that we have not closed the gap, it now appears clear that Referendum 74 will be narrowly approved," said Joseph Backholm, chairman of Preserve Marriage Washington, which worked to defeat the measure.
"We are disappointed in losing a tough election battle on marriage by a narrow margin. But while we are disappointed, we are not defeated."
After crunching their own numbers, backers of the measure on Wednesday declared victory.
Backholm pointed out that Washington is a very liberal state and one of the most secular in the country. He said the polling indicated 80 percent of "unchurched" voters approved of Referendum 74.
Their opponents, he said, had a substantial financial advantage and outspent his campaign by $10 million.
In addition, his campaign was up against what he called "Washington's political establishment and news media — with The Seattle Times taking the unprecedented step of not just endorsing the referendum, but of actively campaigning for its approval."
In what it called a pilot project to test the effectiveness of political advertising in the newspaper, The Seattle Times Co. last month offered discounted political ads to the campaign to approve same-sex marriage.
The ads were an in-kind contribution to the Washington United for Marriage campaign. The newspaper's editorial board also endorsed Referendum 74.
Backholm said despite the loss, "we ran a strong campaign that we can be proud of — a campaign based on honesty and integrity.
"It's a cause worth fighting for, and we will continue to educate citizens and policymakers on the timeless truth that real marriage is the union of one man and one woman," he said.
In the most recent ballot count in Washington Wednesday evening, Referendum 74 was narrowly winning approval, 52 percent to 48 percent.
With incoming ballots from King County increasingly favoring the measure — 67.6 percent Wednesday, up from 65.5 percent on Tuesday evening — it seemed unlikely gay-marriage opponents would gain enough votes to win.
Just to catch up, they would need 54 percent of the estimated 1 million remaining ballots statewide, and more than a third of those are expected to come from King County.
Said Zach Silk, campaign manager for initiative proponents Washington United for Marriage: "This is an historic day for Washington, an historic day for our country and, most of all, for families across the state who have dreamed of this day."
Lornet Turnbull: 206-464-2420 or firstname.lastname@example.org. On Twitter @turnbullL.
STEVE RINGMAN / THE SEATTLE TIMES
After wiping away tears of joy as same-sex-marriage supporters on Wednesday claimed victory for Referendum 74, Jodi Denny of Seattle listens to questions at a news conference in Seattle's Capitol Hill neighborhood.