Voters in the U.S. state of North Carolina have overwhelmingly backed a measure to enshrine the traditional definition of marriage into the state's constitution.
The measure, which also banned same-sex civil unions, passed by 61pc to 39pc. The vote brings the number of states which have voted against same-sex marriage in state referenda to 31. As yet, same-sex marriage has yet to win a referendum in any U.S. state.
Six states -- all in the Northeast except Iowa -- and the District of Columbia allow same-sex marriages. In addition, two other states have laws that are not yet in effect and may be subject to referendums.
Supporters of the amendment welcomed the outcome. The National Organization for Marriage called the result “an overwhelming endorsement of traditional marriage”.
Noting that North Carolina was a crucial swing state in this year's Presidential election, NOM president Brian Brown said the result proved that there was nothing inevitable about same-sex marriage being legalised.
“Just the other day, gay activists were predicting victory in North Carolina, but instead marriage won an overwhelming victory," he said.
He added: "It should not go unnoticed that our position that marriage is between a man and a woman is gaining support, not losing support.
“Earlier this week the Gallup poll showed that support for same-sex marriage is down. Actual vote percentages in favor of traditional marriage are rising. In 2008 in California, the Prop 8 constitutional amendment on traditional marriage passed with 52pc of the vote.
“Then in 2009 in Maine, 53pc of voters stood for traditional marriage and rejected same-sex marriage legislation. In 2010, 56pc of Iowa voters rejected three Supreme Court judges who had imposed gay marriage in that state. And now more than 60pc of North Carolina voters have passed a constitutional amendment defining marriage as the union of one man and one woman. There is a clear trend line, and it is moving in our direction."
North Carolina is the first of five states expected to vote on the definition of marriage this year. Others include Maine, Maryland, Minnesota and Washington.
"We are at the beginning of a national campaign in support of defining marriage as the union of one man and one woman," said Brown.
He said: "Marriage will be a major issue in swing states across the country, and will be directly on the ballot in four more states this fall. The victory in North Carolina is a wonderful beginning to what we believe will be a clean sweep of states this year. We look forward to this national campaign to send an unmistakable message that the American people believe in preserving our historic understanding of marriage."
Meanwhile, President Barack Obama, who went into the 2008 Presidential election saying he believed that marriage should be between a man and a woman has come out in favour of same-sex marriage.
Earlier in his term, his administration said that it would not defend the Defence of Marriage Act, which is a federal law, signed into law by Bill Clinton in 1996 which allows states to refuse to recognise same-sex marriages contracted in other states.
“It is important for me to go ahead and affirm that I think same-sex couples should be able to get married,” Obama said in an interview with ABC News.
His comments marked the first time a US president had publicly expressed support for gay marriage, and his position was hailed by Democrats, gay rights groups.
Others, including Republican activists and conservative Christian leaders, criticised Obama’s stance and called it a huge political risk on a divisive issue.
Some said it could lead independent voters who oppose gay marriage to support Mitt Romney, Obama’s likely Republican opponent in the 6 November election. Noting that 31 states have approved bans on same-sex marriage, they said Obama’s announcement also could help Romney consolidate support among evangelical Christians who, like Romney, oppose gay marriage.