Both sides in the case made clear that they intended to take the case before the Supreme Court in hopes of prompting it to settle once and for all an issue that has been fought out in courts, legislatures and ballot boxes since at least a 1971 case in Minnesota. That said, there is no guarantee the court will take it. The narrow parameters of the ruling’s reasoning — and the fact that it was written to apply only to California — may prompt the court to wait for a clearer dispute before weighing in.

Whatever the legal nuances of the decision — and lawyers were battling about how far-reaching it would prove to be — the decision reverberated throughout political circles, from the presidential campaign to state legislatures.

Mitt Romney denounced the decision as an attack by “unelected judges” on “traditional marriage” and predicted that the Supreme Court would decide the issue. “That prospect underscores the vital importance of this election and the movement to preserve our values,” he said.

Still, the decision by the United States Court of Appeals for the Ninth Circuit, coming at a time when Washington State seems poised to become the seventh state to legalize same-sex marriages, seems likely to add to what members of both parties said was a sense of momentum. Chad Griffin, the president of the American Foundation for Equal Rights, which challenged Proposition 8, noted that polls in the past year had shown public support for same-sex marriage steadily increasing, a significant change from just a decade ago.

In New Jersey, State Senator Stephen M. Sweeney, a Democrat and president of the Senate, who abstained in a vote on a same-sex marriage bill two years ago, is now championing one that is to come up for a vote next Tuesday. “Today’s court ruling simply reaffirmed what we already knew: Marriage equality is right, and its time is now,” he said.