SAN FRANCISCO - City officials have issued marriage licenses to nearly 100 same-sex couples and could unite scores more while opponents are in court today seeking to block the nationally unprecedented nuptials.

While the practical value of the marriage licenses remains unclear, their symbolism was evident - especially on a day when lawmakers in Massachusetts debated a constitutional amendment that would strip gays and lesbians of court-ordered marriage rights. As mandated, they adjourned shortly after midnight today - but without reaching a consensus.

San Francisco's newly elected mayor, Gavin Newsom, directed the county clerk to accept applications from gay and lesbian partners for the first time Thursday - an act of political and legal defiance aimed at challenging California's ban on same-sex marriages.

So many couples took the city up on its surprise offer that, by late afternoon, overwhelmed officials told new applicants to return today. In all, the clerk's office issued 95 marriage licenses to same-sex partners Thursday, and 87 couples took their vows on the spot.

"Even people who are anti-gay marriage might shift their thinking now and realize it's most harmful to take something away when someone already has it," said Virginia Garcia, 40, after wedding Sheila Sernovitz, 50, her partner of 14 years.

The city's bold move, however, caused an outcry from elected officials and groups opposed to marriage rights for same-sex couples.

One group, Campaign for California Families, said it would ask a Superior Court judge today for a temporary restraining order that would enjoin the city from granting any more licenses. The organization also is seeking a ruling from the court declaring the city's actions illegal.

"Those who received the marriage licenses need to know that they are worthless," said Mathew Staver, whose Florida-based law firm, Liberty Counsel, is representing the plaintiffs. "We are confident that they will be invalidated as soon as a judge is able to issue an order."

It was because of a court order that the Massachusetts Legislature convened its constitutional convention, which began Wednesday. The state's Supreme Judicial Court in November ruled it was unconstitutional to ban gay marriage.

Gay and lesbian advocates see the lawmakers' failure to pass an amendment approving civil unions as at least a temporary victory. They condemned the idea of civil unions, arguing it would revert gay people to second-class citizenship after a hard-won court victory.

"We've beaten back three amendments to discriminate," said Sen. Jarrett Barrios, an openly gay Democrat from Cambridge. "We'll see what comes next."

Like their counterparts on the West Coast, conservatives in Massachusetts stood firm.

"The democratic process has been stymied," said Gerald D'Avolio, executive director of the Massachusetts Catholic Conference. "The people at this point have no way to respond to the (court) decision. We had a lot of people who wanted this Legislature, this convention, to give them something to vote on, and that was marriage between a man and a woman."