The vote may be in May, but the campaign surrounding North Carolina's same-sex marriage amendment - a campaign, some say, for the hearts, minds and souls of the state - already has divided the spiritual community.

In Charlotte last week, some lines were drawn by candlelight, during a vigil at Holy Trinity Lutheran Church. Issues that bridge the matters of church and state will surface today in sermons and in Sunday school classes, in private reflections and in prayers.

And that, say religious leaders on both sides, is how it should be.

"In the marketplace of ideas we certainly have a place, and Baptists across the state have been heavily involved, praying and working to get this amendment on the ballot," says the Rev. Mark Harris, pastor of First Baptist Church in Charlotte and soon-to-be president of state Baptist convention.

"We still have a voice in speaking into the lives of our government and on the issues of the day. I will indeed remind our folks, and I believe people across this state will respond."

The Rev. Robin Tanner of Piedmont Unitarian Universalist Church also believes the upcoming vote raises a moral imperative that calls on all religious leaders to act. But that's where their agreement ends.

Harris believes Scripture holds homosexuality as a sin. Tanner calls the proposed amendment an effort to "legislate discrimination."

"When we vote on the rights of others, it becomes a moral and spiritual issue," says Tanner, a lesbian, who moved with her partner to Charlotte in 2010 and now is one of the leaders of the area's Interfaith Equality Coalition.

"We are called as religious leaders to speak with the depth of our faith and to speak truth to power in the face of injustice. If I were to be silent, in some ways it would be easier. But I have the opportunity to speak in behalf of my congregation, to speak up for those who don't have a voice."

The approval of the referendum, only days old, has already become an online flare. An item on charlotteobserver.com calling for worshipers to talk about the issue drew responses from Baptists and Buddhists, Lutherans, Presbyterians, Episcopalians and Catholics.

Lines, long drawn, appear indelible.

Meet Donna Miller, a wife and mother of two who lives in Mint Hill and is a member of Morning Star Lutheran Church.

"I believe I'm well inside my beliefs as a Christian to believe in same-sex marriage," she says.

"This is what I like about the Lutheran church. Above all, you love everyone, and you don't judge."

Meet Chris Ferguson, also married, also from Mint Hill, also a parent of two. A converted Catholic, he attends St. Patrick's in Dilworth.

"People who call themselves Christians actively try to live within the will of God, actively try to center their lives around Christ and his teachings," he says.

"I personally don't see how you can be against a referendum that is based on what we believe."

Denominations take sides

Rancorous debates over homosexual issues, from gay clergy to same-sex unions to more basic disagreements on whether homosexuality is a sin, have divided several major denominations - Episcopalians, Lutherans and Presbyterians among them.

In Charlotte, even the Baptists have faced dissent. In 2007, the state convention expelled Myers Park Baptist from its ranks for welcoming gays and lesbians without trying to change them.

The sweeping popularity of stronger bans on gay unions appears part of a larger effort to hold onto spiritual and cultural ground.

"Forty years ago, it never would have occurred to anyone to put it in the Constitution," says John Green, a senior fellow with the Pew Forum on Religion and Public Life.

"People who strongly believe in traditional marriage do get a sense that the world is changing and they are not happy about that."

North Carolina, which already has a law prohibiting same-sex marriage, will be the last Southern state to vote on the amendment. It would add more restrictions on civil unions and domestic partnerships, and make it much harder for future legislatures to rescind them. South Carolinians passed their constitutional ban in 2006.

Up to now, polls of N.C. voters have been mixed. Voting-day results, though, need little interpretation: Thirty states have voted on the same-sex marriage ban, and 30 have passed it.

Is North Carolina next?

"I wouldn't say it's inevitable," says Lisa Macdonald, who attends Temple Beth El in Charlotte. "I would say it's an uphill fight."

Macdonald and her partner, Becky Stamler, were among seven gay couples who went to Washington, D.C., in April to be married by the three Charlotte ministers accompanying them. On the bus trip back, she says, the group came up with the idea that led to the Interfaith Equality Coalition.

Looking back, she says, she could see the marriage vote coming.

Democrats had blocked the measure for almost a decade. But in November, Republicans took control of the N.C. legislature for the first time in more than a century.

Last week the referendum bill passed.

Afterward, an unusual alliance of Republican lawmakers and black ministers from the Raleigh area turned their attention to the May vote.

"The pulpit will be ground zero, it will be the tip of the spear for leading the charge to defend and protect marriage," said Pastor Patrick Wooden of Upper Room Church of God in Christ in Raleigh.

In Charlotte, Bishop Peter Jugis, head of the Catholic Diocese here, issued a statement expressing his belief "that marriage is created by God as a lifelong union of one man and one woman.

"Since many of the benefits currently being sought by individuals who are not married can already be obtained without regard to marital status, there is no compelling reason to weaken the institution of marriage by opposing this amendment."

Earlier in the week, during the vigil at Holy Trinity Lutheran, other religious leaders preached a different path.

"The good news is that those trying to limit freedom have always been wrong," said the Rev. Jay Leach, pastor of Unitarian Universalist Church of Charlotte.

"Not just wrong to the limit, not just wrong socially, but also wrong religiously. They did not have a divine mandate, and they didn't have justice on their sides."

The pulpit is no stranger to politics, Green says. "Religion - people's faith - can have a powerful effect on people's vote," said Green, author of "The Bully Pulpit: The Politics of Protestant Clergy."

"And ministers and clergy can have a big impact, partly by what they might preach from the pulpit and also from what they do informally.

In Minnesota, Catholic leaders took a more hands-on approach, producing a DVD in support of the marriage ban and distributing it to 400,000 church members.

In the end, Harris says, votes will swing on a church's position on "the inerrancy of the Bible." That leaves little spiritual common ground.

"There's never going to be a resolution to what the Bible says," says Mary McClintock Fulkerson of Duke University's Divinity School.

"You cannot not bring other criteria to how you read the text."

Equality: Race vs. sexuality

At Little Rock AME Zion Church this week, Pastor Dwayne Walker took a question from his Bible group.

What if two church members were gay and wanted Walker to marry them?

"I told them I couldn't do the service," Walker says.

He and his church believe that marriage is reserved for a man and a woman. Homosexuality is a sin, Walker says, but God - and the AME church - love the sinner.

Yet he bristles at the notion that as traditional advocates of social change, black ministers should be more sensitive to discrimination of all forms.

"Racism and somebody's right to marry the same sex? That's as different as night and day," he says.

Walker's reasoning appears to be a common one. When Californians held their same-sex referendum, black voters approved the measure 2-1.

Rodney Sadler, a specialist on black churches at Union Presbyterian Seminary at Charlotte, says black churches were a major force behind the success of the California amendment, and he's quick to point out a certain historical irony.

"In general, African-American churches are in favor of ... making sure everybody's rights are protected," says Sadler, who is black.

"But when we think about issues of sexuality, this commitment to larger rights seems to disappear behind a larger concern for moral purity."

Politically progressive, true, but morally conservative, and uncomfortable, he says, talking about sexuality of any kind.

That's "hurting the community and it's hurting the churches because we aren't able to talk about issues."

In a letter to voters, the Rev. William Barber, president of the state's NAACP chapter, argues that the legislature "is not the modern day Council of Nicaea," referring to the ancient assembly that established a creed for the Christian faith.

"It should not be about religion," Barber said in an interview. "Those are all red herrings ... used to incite false passion."

Walker doesn't expect much passionate debate at Little Rock AME over the referendum, nor does he expect to sermonize on the issue.

His church is clear on where it stands.

"People should have rights," he says. "But we may part on whether they should marry."

Morals meet politics

After the legislative vote, a Democratic state senator lamented the onslaught of a possible "culture war."

Robin Tanner, the Unitarian minister in Charlotte, says all sides must watch their rhetoric, even as they express their feelings.

Likewise, Mark Harris at First Baptist says it's critical how the issues are framed. This is not about bashing homosexuals, he says.

"This is an opportunity to protect marriage from being redefined," a place "where most North Carolinians and Americans don't want to go."

Between now and the May vote, Harris says he'll sermonize on the decision often.

"And I'll remind people of the importance of what we believe."

The Rev. Steve Shoemaker, pastor of Myers Park Baptist - the congregation that Harris and other Baptist conservatives voted to expel in 2007 for its acceptance of gays - says he hasn't made up his mind on how or if he'll address the debate from his pulpit.

That doesn't stop him from calling the referendum a "cynical political use of a moral issue."

"If we legislate into law a specific interpretation of Scripture, we are turning this state into a church," says Shoemaker, who spoke outside the legislature when the referendum bills were introduced this spring.

"In North Carolina, we refused to adopt the Constitution until it had a Bill of Rights. Our state has an ethos of human and individual freedom being very important to us.

"Perhaps that will help us stand differently."

John Frank of the (Raleigh) News & Observer contributed.