Supporters of gay marriage in North Carolina have out-raised and out-advertised their opponents ahead of a vote on May 8 over whether the state constitution should be amended to specifically bar same-sex couples from marrying or entering into domestic partnerships. Despite this effort, 55 percent of North Carolinians say they plan to vote for the amendment in the latest Public Policy Polling figures.

The campaign against the amendment, led by a group called Protect All NC Families, has chipped away at support for the amendment by emphasizing that the change could roll back rights for unmarried heterosexual couples in addition to same-sex couples. They have outspent the pro-amendment side, running TV ads that feature legal experts saying the amendment could make it tougher to prosecute domestic violence cases among unmarried straight couples.

The anti-amendment coalition has raised more than $2 million, according to campaign finance disclosures, most of which came from small and large individual donations. Jeremy Kennedy, the group's campaign manager, says that 75 percent of the individual donations were given by people in North Carolina. The pro-amendment crowd, called Vote for Marriage NC, has raised just over $1 million, with most of the money being donated by nonprofit groups, not individuals.

The amendment started out with a sizable lead, as polls showed that about 61 percent of North Carolinians supported its passage in October. But support has waned, dropping to 55 percent last week, according to Public Policy Polling, a North Carolina-based operation run by a Democratic pollster. The poll found that most voters are confused about the amendment and what it means. Only 40 percent of voters understand that the amendment will also ban civil unions for gay couples, a legal recognition that 55 percent of voters support.

While North Carolina already outlaws same-sex marriage, the state is the last one in the Southeast not to change its constitution to prevent gay unions. The state Legislature, which became majority Republican for the first time since Reconstruction in the 2010 midterm elections, voted to put the matter on the ballot.

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The ballot initiative says that heterosexual marriage is the only valid "domestic legal partnership" in North Carolina. A group of UNC law professors argued in a research paper that the amendment's vague language would strip state and local public employees of benefits for their same-sex or opposite-sex domestic partners, and could lead to conflicts in child custody or domestic violence cases among straight couples who are not married. Rachel Lee, a spokeswoman for the pro-amendment group, told Yahoo News that private companies will still be able to offer benefits to unmarried partners of employees if they want to, and said it's untrue that the statute would complicate domestic violence prosecutions. "They [those against the amendment] never talk about same-sex marriage," Lee said, insisting the opposition isn't plugging gay marriage, but focusing on how the amendment could affect straight people.

Nearly 200,000 people have already cast ballots in early voting, with more Democrats than Republicans voting so far. Kennedy of the anti-amendment coalition says his campaign has focused on recruiting young people on college campuses to vote early, since many will be in the middle of finals next week.

The state's NAACP has come out against the amendment, becoming only the second state NAACP chapter to oppose a gay marriage ban. However, just over half of black voters support the amendment, according to Public Policy Polling numbers. The Charlotte Observer wrote that leaders of some majority black churches, including a megachurch of 6,000 members, have urged their parishioners to vote for the amendment. Lee says the pro-amendment group has partnered with more than 6,000 churches.

But not everyone is taking sides. Some major business owners and the state's Chamber of Commerce are staying neutral.

Still, tensions are running high and occasionally the campaign has gotten ugly. On Monday, the Vote for Marriage NC group accused an unnamed gay marriage supporter of attacking one of their supporters with a car door because she had a pro-amendment sign in her yard. Lee wouldn't provide any details about the accusation, and a spokesman at the Robeson County Sheriff's Office told Yahoo News he hadn't heard anything about the incident. Later on Monday, an amendment supporter uploaded a video of him shooting an anti-amendment sign repeatedly. Kennedy says a gay marriage supporter with an anti-amendment bumper sticker had the word "fag" spray-painted on his car by an unknown vandal.

So far, 31 states have passed ballot initiatives banning gay marriage, and no ballot initiative on the issue has ever failed. But gay rights advocates are hoping that might change, if not in North Carolina than in one of the states that will face a vote this year. Americans' support for gay marriage has grown rapidly, with the latest polls showing that the nation is divided evenly on the issue. Voters will most likely have a chance to reverse same-sex marriage laws that recently passed in Maryland and Washington come November. And Minnesota faces its own gay marriage ban this election, while in Maine, activists took the unusual step of proactively putting gay marriage on the ballot, hoping that voters have changed their minds on the issue since 2009, when they repealed a gay marriage law.

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