More than 18 months after Obergefell v. Hodges brought marriage equality to all 50 states, North Dakota still refuses to accept same-sex marriage as a reality.

On Tuesday, lawmakers in the Republican-controlled state Senate rejected a bill changing the language in official documents from "husband and wife" to gender-neutral terms.

Failing 15-31, the measure would have updated references on everything from marriage certificates to fishing licenses.

Back in 2004, 73% of North Dakota voters approved a state constitutional amendment defining marriage as between one man and one woman. It was invalidated by the Supreme Court's ruling, but obstinate Republicans have held off revising all the paperwork.

Democratic Sen. John Grabinger said he was concerned the state has been left open to lawsuits, since "same-sex marriage is the supreme law of the land."

But Republican state Senator Kelly Armstrong, chairman of the Judiciary Committee, balked, calling it a "pretty drastic overestimation that we would end up in litigation if we don't pass this bill."

North Dakota legislators have repeatedly voted against banning discrimination based on sexual orientation or gender identity, most recently in 2015.