Michael Wyke / Tulsa World Married partners Gay Phillips (with Pride flag) and Sue Barton, along with unmarried partners Sharon Baldwin and Mary Bishop, pictured at a June panel discussion, brought the suits that were upheld Tuesday.

Oklahoma's ban on same-sex marriage was struck down Tuesday by a federal judge who declared it a fundamental violation of equal rights.

U.S. Senior District Judge Terence Kern ruled in Tulsa that a state constitutional amendment limiting marriage to opposite-sex couples ran afoul of the U.S. Constitution's guarantee of equal protection under the 14th Amendment.

The ruling won't immediately let same-sex couples get married in Oklahoma, however. Kern stayed the ruling pending resolution of a similar challenge to Utah's ban on same-sex marriage, which is being heard by the 10th U.S. Circuit Court of Appeals in Denver.

"We're pretty elated," Sharon Baldwin, one of the plaintiffs suing to overturn the ban, told NBC station KJRH of Tulsa. "It's been a long time coming."

But Gov. Mary Fallin said she was "disappointed," noting that the restriction was passed by Oklahoma voters nine years ago with 75 percent support.

"The people of Oklahoma have spoken on this issue," Fallin said in a statement. "I support the right of Oklahoma's voters to govern themselves on this and other policy matters."

The case, Bishop et al. v. United States (.pdf), involves two couples who challenged Oklahoma's ban in 2004.

One of the couples who brought the suit has been "in a loving, committed relationships for many years," Kern wrote in a 68-page opinion. "They own property together, wish to retire together, wish to make medical decisions for one another, and wish to be recognized as a married couple with all its attendant rights and responsibilities."

But they are excluded from marriage, he wrote, "without a legally sufficient justification."

Kern called Oklahoma's ban "an arbitrary, irrational exclusion of just one class of Oklahoma citizens from a governmental benefit," declaring:

"Equal protection is at the very heart of our legal system and central to our consent to be governed. It is not a scarce commodity to be meted out begrudgingly or in short portions."

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The case involves two couples — Baldwin and Mary Bishop, and Gay Phillips and Susan Barton — who challenged Oklahoma's ban in 2004 in a lawsuit that also challenged the federal Defense of Marriage Act, or DOMA. A trial had been scheduled for May 2012, but it was put on hold while other same-sex marriage worked their way through the federal courts.

Kern ruled only on the part of the suit addressing the Oklahoma state constitution, noting that the key provision of DOMA has already been declared unconstitutional.

Bishop, assistant editor of The Tulsa World, and Baldwin, a city editor at the newspaper, exchanged vows in a commitment ceremony in Florida in 2000. In 2009, they were denied an Oklahoma marriage license.

Barton, a doctor of sociology, and Phillips, an adjunct professor at Tulsa Community College, have been a couple since 1984 and were married in Canada in 2005 and in California in 2008.

Like Baldwin in Oklahoma, Peggy Tomsic, a lawyer for the plaintiffs seeking to overturn the Utah law, said Tuesday that she, too, was "thrilled" by the ruling.

"This is yet another powerful indication of the growing recognition that these discriminatory laws cause serious harm to real families, while benefiting no one,” Tomsic said.

But Brian Brown, president of the National Organization for Marriage, which opposes same-sex marriage, said the ruling illustrated "the dangers posed to state marriage laws when the avenue of debate is the federal court system."

Brown said the organization was redoubling its campaign for an amendment to the U.S. Constitution defining marriage as between a man and a woman.

Pete Williams of NBC News contributed to this report.

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