"There are many same-sex spouses who married elsewhere who now live in Maryland," said National Center for Lesbian Rights Legal Director Shannon Minter. "This ruling ensures that they have all the same rights as any other married couple in Maryland. This is a powerful decision that will provide enormous security and protection to thousands of families."

Susan Sommer, director of constitutional litigation at Lambda Legal, said, "The high court of Maryland confirmed today in this divorce case that out-of-state marriages of same-sex couples are entitled to legal recognition under longstanding principles of comity, allowing this couple the same access to a divorce as other married couples whose relationships have ended."

While the case highlights state differences in the recognition of same-sex marriages, analysts have said it will probably have little influence outside Maryland because federal law allows states to ignore how other states define marriage.

"This is simply going to be a case about the Maryland state constitution," said Mark A. Graber, a law professor at the University of Maryland School of Law.

Gay rights activists say the matter often leaves same-sex couples in legal limbo when moving between states, claiming that Maryland state courts have also inconsistently ruled on issues relating to same-sex marriages.

"Divorce is never easy, but when a couple has made the decision to end their marriage, there is no reason why the state should prevent them from ending their legal relationship and moving on with their lives," said Erik Olvera, a spokesman for the National Center for Lesbian Rights.

Maryland Gov. Martin O'Malley signed into law a bill that allowed same-sex couples to wed. The law, however, isn't scheduled to take effect until January 1.

The measure's opponents have pledged to challenge it by holding a referendum during November's election.

The Maryland Marriage Alliance group says it's gathered thousands of signatures and is approaching the threshold required to put the issue on the ballot, adding further uncertainty to the Port and Cowan case.

"If anything, it shows the nuttiness of the interim period," Graber said of the unclear nature of Maryland state law in apparent transition.