In the meantime, gay-marriage supporters continue their years-long battle in the state courts. In January, Christie added an interesting twist: He nominated an openly gay man to the state Supreme Court.
The nominee, Bruce A. Harris, 61, mayor of Chatham, has said he would recuse himself from the same-sex marriage case - a frustration for gay-marriage advocates.
"I support Bruce Harris' nomination for the great diversity it would bring to the Supreme Court; true history for the LGBT community," said Steven Goldstein, chairman of the state's largest gay rights organization, Garden State Equality.
"Do I believe that Bruce Harris should recuse himself on a marriage equality case? No. No more than I believe that a judge who is a woman should recuse herself on a case involving the civil rights of women, no more than I believe that a judge who is a person of color should recuse him or herself from a civil rights case involving people of color."
Same-sex marriage advocates have secured substantial victories in New Jersey compared with Pennsylvania. New Jersey first recognized domestic partnerships in 2004 and began granting civil unions in 2007.
The advocates hope Obama's support will persuade more legislators and judges to consider allowing gay couples the right to marry.
"It's a powerful recognition from a president . . . that anything other than equality and access to marriage for committed loving couples won't do," said Hayley Gorenberg, lead counsel on the lawsuit and deputy legal director of Lambda Legal, a group that litigates gay rights issues.
The state Democratic Party used Obama's pirouette to ask for money.
"I hope you would consider a contribution of $100, $75, $50, or even $35 to the New Jersey Democratic Party," read an e-mail sent out by Chairman John Wisniewski, "so that we can continue holding Chris Christie's feet to the fire on the issue of marriage equality for New Jersey."
New Jersey passed the civil union law after the state Supreme Court ruled unanimously that same-sex couples should be given the same rights as married couples.
But a commission that studied the issue in 2008 determined that civil unions do not provide the equality the court mandated. Couples have struggled to make medical decisions for their partners, access spousal benefits, and even secure mortgages.
"All our clients are allowed to do is get a civil union, and that's not cutting it," Gorenberg said.
A new lawsuit, filed in June - again seeking marriage rights - is in Superior Court in Mercer County and headed for trial in 2013, Gorenberg said. It could take years for the case to reach the Supreme Court, where only two of the justices who ruled on the 2006 case remain on the bench.
Hearings on Harris' nomination are expected this month.
Appointing Harris is seen as a deft political move for Christie, who governs a left-leaning state and who has a growing national profile.
Christie conditionally vetoed the gay-marriage bill in February, offering instead to appoint an ombudsman who would oversee civil unions and help unravel any problems same-sex couples faced.
And although a majority of New Jerseyans who responded to recent polls support gay marriage, legislative leaders and gay rights advocates are opposed to putting gay marriage as a ballot question in a referendum, a vehicle used in dozens of states to ban gay marriage.
"Referenda are not tests of popular will; they're tests of fund-raising," Goldstein said in a statement. "It's time for our governor . . . to stop telling you that a referendum would let the people decide. No, it won't; it would let PACs and political consultants decide."
Sweeney, who helped resurrect marriage equality two years after a similar measure failed, said Obama's support of gay marriage would help persuade more lawmakers to vote for the bill when it comes up again. Sweeney is himself a convert: He abstained from voting in 2010, when the gay rights bill failed, 20-14, in the Senate.
Supporters need a two-thirds vote in both chambers to override Christie's veto: That's an additional three votes in the Senate and a dozen in the Assembly. Sweeney believes Republican legislators might lean his way after they have secured reelection in 2013.
At a town-hall meeting in Franklin Township on Thursday, Christie said his position on gay marriage wouldn't change. "I just do not believe that marriage should be between anyone but a man and a woman," Christie said, according to the Newark Star-Ledger.
Goldstein said Christie's opinion may not matter in the long run.
"Obviously, we realize that a staunch Republican with a national profile in his party won't give a damn what Obama said or does," Goldstein said. "But the people will, and that will be the ultimate impact on Gov. Christie, even if he doesn't yet realize it."
Contact Joelle Farrell at 856-779-3237, firstname.lastname@example.org, or follow @joellefarrell on Twitter.