NEW YORK — Even as they celebrate a momentous legal victory, supporters of gay marriage already are anticipating a return trip to the Supreme Court in a few years, sensing that no other option but a broader court ruling will legalize same-sex unions in all 50 states.
In the meantime, as one gay-rights leader said, there will be "two Americas" — and a host of legal complications for many gay couples moving between them.
Wednesday's twin rulings from the high court will extend federal recognition to same-sex marriages in the states where they are legal, and will add California — the most populous state — to the 12 others in that category. That will mean about 30 percent of Americans live in states recognizing same-sex marriage.
But the court's rulings have no direct effect on the constitutional amendments in 29 states that limit marriage to heterosexual couples. In a handful of politically moderate states such as Oregon, Nevada and Colorado those amendments could be overturned by ballot measures, but that's considered highly unlikely in more conservative states.
"It would be inefficient to try to pick off 30 constitutional amendments one by one," said Fred Sainz of the Human Rights Campaign, a national gay-rights group. "Eventually this will have to be settled by the Supreme Court."
The Human Rights Campaign's president, Chad Griffin, told supporters outside the Supreme Court building that the goal would be to legalize same-sex marriage nationwide within five years.
To sway the justices in such a time frame, activists plan a multipronged strategy. In addition to possible ballot measures in a few states, they hope lawmakers will legalize same-sex marriage in states which now offer civil unions to gay couples, notably New Jersey, Illinois and Hawaii.
There also will be advocacy efforts in more conservative states, ranging from expansion of anti-discrimination laws to possible litigation on behalf of sex-couples there who are denied state recognition even though they married legally in some other jurisdiction.
The Supreme Court's decisions "underscore the emergence of two Americas," Griffin said. "In one, LGBT (lesbian, gay, bisexual and transgender) citizens are nearing full equality. In the other, our community lacks even the most basic protections."
Jonathan Rauch, a senior fellow with the Brookings Institution think tank in Washington, suggested that efforts to end that division would not be easy, given that many states have electorates that seem solidly opposed to gay marriage.
"The fight is far from over," Rauch wrote in a commentary. "By refusing to override those majorities, the court green-lighted the continuation, probably for a decade or more, of state-by-state battles over marriage."
In Florida, where voters approved a ban on gay marriage with 62 percent support in 2008, the gay-rights group Equality Florida called on its supporters to "get engaged and fight" for recognition of same-sex marriage.
The high court rulings "are a major step forward for the country, but for Floridians they fall far short of justice," said the group's executive director, Nadine Smith. "The Supreme Court has said we can go states like Minnesota or Iowa and get married, but we return to Florida legal strangers in our home state."
Florida State Rep. Joe Saunders, a Democrat from Orlando and one of the state's first openly gay lawmakers, said "every strategy is on the table" as activists ponder ways to eliminate the 2008 ban, including warnings of economic consequences.
"If 13 other states provide protections to gay and lesbian families, what does that mean for our ability to keep those families here in Florida?" he said. "Until we can promise them the same basic protections, we're going to be economically disadvantaged."
Increasingly, political swing states like Florida, as well as more solidly Republican states, could become gay-marriage battlegrounds.
One example of the forthcoming strategy: The American Civil Liberties Union announced Wednesday that it has hired Steve Schmidt, former communications director for the National Republican Congressional Committee and adviser to Sen. John McCain, R-Ariz., to build support among GOP state politicians for striking down gay-marriage bans.
"For a full civil liberties victory, we need broad-based support from coast to coast," the ACLU's executive director, Anthony Romero, said.
On the conservative side, there was deep dismay over the Supreme Court rulings, but little indication of any new strategies or initiatives.
"The debate over marriage has only just begun," said Austin Nimocks, senior counsel with Alliance Defending Freedom, a conservative legal group.
The U.S. Conference of Catholic Bishops, which staunchly opposes same-sex marriage, called upon Americans "to stand steadfastly together in promoting and defending the unique meaning of marriage: one man, one woman, for life."
Lee Badgett, an economics professor at the University of Massachusetts, predicted that the ruling on federal recognition would prompt thousands of gay couples to get married, now that there were additional financial incentives to so.
This group could include couples in states which don't recognize same-sex marriage but who are willing to travel to a state that does recognize such unions.
However, Rea Carey of the National Gay and Lesbian Task Force said many gay couples either would be hard pressed to afford such trips or would forgo them out of principle.
"Many people in this country, straight or gay, want to get married in their own state, their own backyard," she said.
While gay-rights activists pursue their ultimate goal of nationwide recognition of same-sex marriage, the short-term legal situation for many gay couples could be complicated.
Peter Sprigg of the conservative Family Research Council said the court ruling on federal recognition "raises as many questions as it answers."
"Will recognition be based on the law in the state where the marriage was celebrated or the state in which the couple resides?" he said. "The doors may now be wide open for whole new rounds of litigation."
The National Conference of State Legislatures said the situation was clear for married gay couples in the 13 states recognizing same-sex marriage: They will be eligible for all federal marriage benefits.
"Outside of these states, federal marriage benefits become more complicated, as many commonly thought-of federal benefits, such as jointly filing on federal income taxes, are tied to a married couple's place of residence," the conference said.
Gay-rights activists immediately began lobbying the Obama administration and other federal officials to extend as many benefits as possible on the basis of where a gay couple's wedding took place, not on the state where they live.
"The Obama administration can make clear, through regulation, that the federal government will recognize those marriages and not participate in state-sponsored discrimination," said Suzanne Goldberg, a professor at Columbia Law School.
Evan Wolfson of Freedom to Marry, one of the groups most active in building support for same-sex marriage, urged the administration to adopt a "clear and consistent" standard that would apply equally to all married gay couples, regardless of their state of residence.
"Marriage should not flutter in and out like cellphone service," he said. "When it comes to federal programs, even if states are discriminating, the federal government should not."
Wolfson, like many of his allies, was already looking ahead to another rendezvous with the Supreme Court, confident that public support for same-sex marriage would continue to increase.
"We have the winning strategy," he said. "We win more states, we win more hearts and minds, and we go back to the Supreme Court in a matter of years, not decades, to win the freedom to marry nationwide."