The North Carolina House of Representatives has approved an amendment to the state constitution that would define marriage as solely between one man and one woman.

The Republican-controlled House passed the proposed amendment in a 75 to 42 vote on Monday after a three-hour debate. If the state Senate also approves the proposed amendment, North Carolina voters would ultimately decide its fate in a statewide referendum on next May's primary date.

State law already defines marriage as between one man and one woman, but a constitutional amendment would protect the law from legal challenges.

"Things have changed in Iowa, California, New York, D.C. and Massachusetts," House Majority Leader Rep. Paul Stam (R) said. "We have now states with significant populations that are allowing same sex marriages to be legitimized and entered into. The question then becomes what happens when they come to North Carolina seeking divorce or equitable distribution?"

Stam previously said same sex marriage needed to be banned to protect children, and that any argument used to support same sex marriage could be used to support the practice of polygamy and incest.

Democrats have mostly opposed the amendment, and accused Republicans of having priorities that are "seriously out of whack."

"The reality is that this amendment will not put one person back to work, it will not help one small business keep its doors open and it will not assist one single citizen now trying to recover from the devastation inflicted by Hurricane Irene," David Parker, Chairman of the North Carolina Democratic Party said in blog post.

"It is simply un-American to single out any group of law-abiding citizens to harass and torment," he added. "Every time we select a set of folks to exclude from America's dream of a better life, the results are detrimental to our nation."

The proposed amendment would allow companies to offer benefits to employees in domestic partnerships, but some law professors have warned that the language could invalidate domestic violence laws and disrupt child custody cases.

"We are going to be enacting language into the constitution that no one knows what it means and could hurt citizens of this state and that will take years of needless litigation to resolve the meaning," Maxine Eichner, a law professor at the University of North Carolina School of Law in Chapel Hill, told the Associated Press.