Gay rights advocates said they were heartened after both candidates for governor of New Jersey stated they would oppose a constitutional ban on same-sex marriage, but a day after those declarations, their campaigns declined to specify what either man would do if the state Supreme Court allows such unions.

In a recent debate, gubernatorial candidates Doug Forrester and Jon Corzine found common ground on the issue. Both said they oppose same-sex marriage, but that they would oppose a constitutional amendment banning it.

Their positions could be tested next year, when the state Supreme Court is expected to rule on a lawsuit from several same-sex couples who claim the state constitution gives them a right to marry. Arguments have not been scheduled in the case and are likely to be heard sometime after the Nov. 8 election.

In the debate, both candidates gave a nuanced and nearly identical view on same-sex marriage.

From Corzine, a Democrat: “I believe [that] the fundamental and traditional view of marriage is between a man and a woman. On the other hand, I don’t believe constitutions are about taking away rights. That’s why I wouldn’t have supported an amendment in the federal government and I won’t support one in New Jersey.”

From Forrester, a Republican: “I believe that marriage is between a man and a woman. I believe that a constitutional amendment isn’t the right tool to make that defense.”

When pressed for clarifications, the campaigns had little to say.

Lower courts have twice held that same-sex couples do not have the right to marry in New Jersey, but court-watchers on both sides of the issue think there’s a good chance the state Supreme Court will overturn those rulings.

Corzine spokesperson Ivette Mendez said she would not answer questions about what Corzine would do in that case, saying they were “hypothetical”

Forrester spokesperson Sherry Sylvester said Forrester believes the same-sex marriage decision should be made by elected lawmakers, not appointed judges. And if judges allowed same-sex matrimony, she said, he would “take any steps to return the debate to the Legislature, where he believes the decision should be made.”

She would not specify those steps, though, and reiterated that Forrester opposes a constitutional ban on same-sex marriage.

Same-sex marriage opponents say that such a ban is their best hope of preventing the unions in New Jersey, which is one of a handful of states to recognize domestic partnerships.

Rick Merkt, the Republican state Assembly member from Morris County who is the sole sponsor of a constitutional amendment that would make it the Legislature’s decision whether to allow same-sex marriage, said he thinks the court will allow same-sex marriage and, especially without a governor’s support, lawmakers won’t override such a decision.

“I suspect the Legislature will tuck its tail between its legs and be glad it didn’t have to make the hard decision,” Merkt said.

An amendment to the state constitution requires passage by both houses of the state Legislature and a vote by the public.

The governor does not have a formal role in the process.

But, said Steven Goldstein, chair of the gay rights organization Garden State Equality, “the governor, whoever it may be, will have a huge bully pulpit.”

Goldstein said he is not aware of a state where both major-party candidates for governor have opposed a constitutional amendment banning same-sex marriage. “If the state Supreme Court decides to rule in favor of gay marriage, there’s a very strong shot that we in New Jersey won’t have to go through the years of legislative threats that are going on in Massachusetts,” he said.