Just weeks after winning the right to marry, dozens of same-sex couples took part in a symbolic commitment ceremony in West Hollywood.

But Wednesday night's event wasn't just a celebration of love and a court victory. It also was a vow to keep fighting, because a ballot measure in November could take away what was won.

"I take nothing for granted," said Sonora Chase, 35, who participated in the event with her partner Dasha Snyder, 37. The couple plans to marry in the coming months, but say they are proceeding knowing their union could be invalidated if the measure passes.

This was a third year in a row that The Abbey, a popular lounge, kicked off Gay Pride month in Los Angeles with such a ceremony.

Faded pink rose petals sprinkled the white carpet as a guitarist performed Pachelbel's "Canon in D." The crowd of family and friends gathered in support as their loved ones stood in front of the mayor of West Hollywood to take a vow.

"Your joined hands are outward and visible signs of an inward and spiritual bond," Mayor Jeffrey Prang said, "signifying to all your commitment to each other and your commitment in vowing to vote and protect your right to love."

Then, before a cadre of television celebrities and the family of a modern gay rights martyr, the couples sealed the pledge with kisses.

Earlier Wednesday, the California Supreme Court refused to stay its May decision legalizing gay marriage. Counties must begin issuing new gender-neutral marriage licenses on June 17.

An initiative to ban gay marriage has qualified for the Nov. 4 ballot. Its passage would overrule the court's decision by amending the state constitution to limit marriage to a man and a woman.

John Manelski, 30, and Jordan Brusso, 26, expressed optimism the measure would fail in November. Just in case, they said they have planned a legal ceremony in September and will have a big celebration next May.

"We want to get it done before November," Brusso said. "We don't have enough time to plan the wedding we want to have."

Like many high-profile causes, the event drew celebrities who in this case served as witnesses. "Grey's Anatomy" co-star T.R. Knight hosted the event accompanied by his boyfriend, Mark Cornelsen, but they did not join the other couples marching down the white carpet to exchange vows.

"There's a lot of hate around and until that hate disappears, you're going to have people trying to push down another group of people for whatever reason," Knight said.

Fresh from "The Tonight Show" set and a March dustup over a show in which he asked actor Ryan Phillipe to portray his "gayest face," Jay Leno dropped by briefly to lend support.

"I have friends in the gay community. Who doesn't know gay people in Hollywood?" Leno joked.

Wednesday's event also had a commercial sponsor and a designated cause, the Matthew Shepard Foundation, the nonprofit established by the family of the University of Wyoming student who was beaten to death in 1998 by two men who suspected he was gay.

New York jewelry designer Udi Behr gave participating couples titanium pendants engraved with the words "Erase Hate" - the foundation's slogan. Behr, who designs a line of wedding rings for same-sex couples, said business was good. He seemed less upbeat, though, about the country's gay-rights struggle - even in the wake of the decision of the state's high court.

"It's a drop in the ocean," Behr said. "There is a lot more to do."

Matthew Shepard's mother, Judy, provided a poignant reminder of how much the gay rights movement had gained since his murder and of how much remained at stake. She recalled sitting with her son in his apartment the summer before his death and having him ask whether she thought gay men and lesbians would be able to marry in his lifetime.

"I said, 'Not in my lifetime, but definitely in yours,"'

Shepard recalled. "It happened in my lifetime, not his."