James Gibbard, Tulsa World (AP) Gay Phillips, left, her partner Sue Barton, and Mary Bishop and her partner Sharon Baldwin have a champagne toast during a celebration at the Dennis R. Neill Equality Center, Tuesday, Jan. 14, 2014 in Tulsa, Okla., after a federal judge struck down Oklahoma's gay marriage ban. Photo:

James Gibbard, Tulsa World (AP) Gay Phillips, left, her partner Sue Barton, and Mary Bishop and her partner Sharon Baldwin have a champagne toast during a celebration at the Dennis R. Neill Equality Center, Tuesday, Jan. 14, 2014 in Tulsa, Okla., after a federal judge struck down Oklahoma's gay marriage ban. Photo:

TULSA, Oklahoma — For the second time in a month, a federal judge has set aside a deeply conservative U.S. state’s limits on same-sex marriage, this time in Oklahoma.

Like the federal judge who reversed Utah’s gay marriage ban in December, U.S. District Judge Terence Kern on Tuesday determined that Oklahoma’s voter-approved ban on same-sex marriage violated the U.S. Constitution’s equal protection clause.

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

Oklahoma’s ban on same-sex marriage is the third to be struck down by a federal judge, after California and Utah. State courts also ruled in favor of same-sex marriage in New Mexico in December and New Jersey in October.

Camilla Taylor, marriage project director at the national civil rights organization Lambda Legal, said momentum has been i ncreasing as litigators see that gay rights groups are winning same-sex marriage cases. She said there are currently 43 gay marriage lawsuits in courts, and a new one is brought almost every week.

Not including Utah and Oklahoma, 27 states still have constitutional prohibitions on same-sex marriage. Four more – Indiana, Pennsylvania, West Virginia and Wyoming – do not permit it through state laws.

For 17 days, Utah was the 18th state to allow gay couples to wed, after the surprise ruling in December. Hundreds of couples got married before the U.S. Supreme Court put a halt to the weddings earlier this month while a lower court considers the issue.

The fate of gay marriage in Utah now rests in the hands of the 10th Circuit Court of Appeals – the same circuit as Oklahoma, where state and local officials are working on an appeal of Tuesday’s ruling.

Oklahoma Attorney General Scott Pruitt said the Supreme Court had left it to the states to define marriage and that Kern’s ruling was “troubling.” He said it would likely take another Supreme Court decision to resolve the matter.

The Oklahoma ruling came in a lawsuit filed nearly a decade ago, by two same-sex couples.

“There’s so much emotion, I’m kind of crying right now,” said Mary Bishop, who hopes to marry partner Sharon Baldwin. “It’s overwhelming to think that we finally won.”

Taylor, with Lambda Legal, said she wasn’t sure why the judge’s ruling came now, though she noted that his ruling made several references to the Utah case.

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