SEATTLE - Same-sex couples in Washington state began reciting wedding vows at events across the state Sunday, on the first day they could marry after the state's gay marriage law took effect.

About 140 couples had registered to marry at Seattle City Hall, which had set up five chapels to accommodate the revelers. Starting at 10 a.m., cheers and applause regularly broke out as another couple's marriage became official. Weddings at city hall were to continue through 5 p.m.

"We're totally thrilled," said Keith Bacon, who celebrated his six-year anniversary with Corianton Hale the night before. The couple had done a commitment ceremony in August but said this day was special.

"We had looked at this as maybe a day we would sign a piece of paper and seal the deal, and instead we're having this huge party being thrown in our honor," Bacon said. "It's just mind blowing."

The couple hugged and kissed to loud cheers and camera flashes as they took their vows before one of the 16 local judges who volunteered to officiate the weddings on Sunday.

Nancy Monahan, 57, a retired petty office with the Coast Guard, waited outside before the weddings began with her partner of 14 years, Deb Needham, 48. They said they wanted to join the large wedding event at city hall because of the significance of the day.

"It's not very private, but very historic," Needham said, to which Monahan added, "And very awesome."

Some courthouses, including in King and Thurston Counties, opened at midnight, and started marrying couples. Hundreds of couples picked up their marriage licenses as early as 12:01 a.m. Thursday, but because of the state's three-day waiting period, the earliest that weddings could take place was just after midnight, early Sunday morning.

At the Thurston County Courthouse five couples were married, including Jonathon Bashford, 31, and Matthew Wiltse, 29, both of Olympia. The couple, together for 10 years, just had a large commitment ceremony in September when they registered as domestic partners, but said they wanted to be among the first to legally marry.

"We weren't going to wait one second longer," Wiltse said.

Last month, Washington, Maine, and Maryland became the first states to pass same-sex marriage by popular vote. They joined six other states - New York, Connecticut, Iowa, Massachusetts, New Hampshire, and Vermont - and the District of Columbia that had already enacted laws or issued court rulings permitting same-sex marriage.

Couples in Maryland also started picking up marriage licenses Thursday, though their licenses won't take effect until Jan. 1. Maine's law takes effect Dec. 29. There's no waiting period in Maine, and people can start marrying just after midnight.

Washington Gov. Chris Gregoire and Secretary of State Sam Reed certified the election results of Referendum 74 on Wednesday afternoon, and the law took effect at 12:01 a.m. Thursday. The marriages of same-sex couples who had wed in another state became valid here as soon as the law took effect.

The referendum had asked voters to approve or reject the state law legalizing same-sex marriage that legislators passed this year. That law was signed by Gregoire in February but was put on hold pending the outcome of the election. Nearly 54 percent of voters approved the measure.