A landmark law legalizing same-sex matrimony took effect in Washington state on Thursday as gay and lesbian couples lined up at government offices to obtain marriage licenses, paving the way for them to exchange vows as soon as this weekend.

Washington, Maine and Maryland became the first three U.S. states to extend marriage rights to same-sex couples by popular vote, with passage of ballot initiatives on November 6.

Washington was the first to hand out marriage license applications to gay and lesbian couples, starting at 12:01 a.m. on Thursday. Maine and Maryland's laws take effect on December 29 and on January 1, respectively.

But the earliest same-sex Washington weddings - expected to number in the hundreds - will not take place before Sunday because of a state requirement that all couples submit their licenses three days in advance.

In Olympia, the state capital, Lisa Brodoff and Lynn Grotsky, partners of nearly 32 years, became the first same-sex couple in their county, and perhaps the state, to receive a marriage license on Thursday - to the cheers of a crowd of other gay and lesbian couples and supporters.

"We have the greatest feeling of happiness and relief and excitement," said Brodoff, 57, a law professor at Seattle University.

Grotsky, 56, a social worker, said that when she and Brodoff became a couple, they were afraid to tell acquaintances and co-workers that they were lesbians.

"Everything was a fight and a conflict," Grotsky said. "Now it's like we're regular people."

The pair, who hugged and kissed after getting their license, could have exchanged vows in one of the six states where same-sex marriage is already legal. But they wanted to wait until they could marry in their home state.

Thurston County Auditor Kim Wyman, whose office opened at midnight to serve 15 couples seeking to be the first in the state capital to obtain licenses, called the moment historic.

"Some of these couples have been together for more than 20 or 30 years. It's pretty moving when you hear those stories," she said.

SAVING THAT DATE

The Democratic-controlled state legislature passed a bill to legalize gay marriage in February, and Democratic Governor Christine Gregoire swiftly signed it into law.

But opponents collected enough signatures to temporarily block the measure from taking effect and force the issue onto the state ballot in November. Voters passed it by 54 percent to 46 percent.

A spokesman for Seattle Mayor Mike McGinn said the mayor would be on hand to greet 140 couples coming to get married at City Hall on Sunday.

"It's a great day," spokesman Aaron Pickus said. "Seattle voted overwhelmingly for marriage equality. It just shows once again that everyone is welcome here."

Marji Lynn, a telecommunications company manager, and Sue Hopkins, a writer and artist, will be among the couples married at Seattle City Hall on Sunday. Unlike many other couples planning to wed under the new law, the pair - together for 16 years - never registered as domestic partners.

"That seemed like a half-step, and we really wanted to be married," Lynn said. "And we wanted to wait until it was legal in Washington."

Olympia residents Tina Roose and Teresa Guajardo said they would wait until December 15 to marry, having reserved the majestic state Capitol rotunda for a pre-Christmas wedding ceremony.

The uncertainty of the ballot initiative process forced Roose and Guajardo to wait until after the election to see if they could keep their reservation.

Roose, a retired librarian, said the couple had invited others, gay and straight, to tie the knot alongside them at the Capitol.

"I just ran into a colleague today at a grocery," she added. "She was so excited. She asked all the typical questions like, 'What are you going to wear?'"

As for those who voted against same-sex marriage, Roose said she hoped they would be won over "with love."

"You can only change people's attitudes one heart at a time," she said.