Speaking recently to a group of black evangelical ministers and lay people here, Genevieve Wood of the conservative Family Research Council made an impassioned plea. Black Christians, she said, must speak out against advocates of gay marriage.
"They are wrapping themselves in the flag of civil rights," said Ms. Wood, who is white, as visitors from across the country shook their heads in dismay. "I can make arguments against that. But not nearly like you all can."
As Ms. Wood has been brokering alliances to oppose gay marriage, Donna Payne, a board member with the National Black Justice Coalition, a black gay and lesbian organization formed to increase acceptance of gay rights among African-Americans, has been appealing to liberal black clergy members. Reaching out to potential supporters, like the Rev. Abena McCray of the Unity Fellowship Church in Washington, Ms. Payne argued that recognizing gay marriage was a matter of equal rights.
"We have to find ministers who will stand with us," Ms. Payne said, while going through her list of contacts. "We have to at least try to bring some balance to the discussion."
As debate escalates around same-sex marriage, advocates on both sides are busily seeking support from the same source: black clergy members. Though their pitches are polar opposites, their motives are largely the same. Each seeks the perceived moral authority and the sheen of civil rights that black religious leaders could lend to each cause.
But the aggressive outreach is rife with complications. Neither white conservatives nor gay-rights advocates have had great success in sustaining broad alliances with black churches in the past.
The fact that many black Christians are both politically liberal and socially conservative makes them frustratingly difficult to pigeonhole in a political environment in which, many pundits contend, voters are cleanly split along ideological lines. Many blacks opposed to gay marriage, for example, support equal benefits for gays as a matter of economic justice.
And the prize often generically referred to as "the black church" is actually a diverse collection of historically black denominations and congregations that covers a wide range of theological and social beliefs.
Advocates of gay marriage are appealing to those on the left end of that spectrum to show that the issue is really about civil rights. Those opposed are courting more conservative blacks as evidence that they are not bigots for suggesting the issue has nothing to do with civil rights. The resulting alliances are often used publicly to imply backing of "the church" as a whole.
Still, the battle for the soul of the black church is in full swing. President Bush's call last week for a constitutional amendment banning gay marriage has accelerated efforts.
A day after the president's remarks a group of black Baptist ministers in Chicago held a news conference applauding his stance. It was the first of several such events in coming weeks planned by black conservative clergy members as a result of the meeting with Ms. Wood.
"If the K.K.K. opposes gay marriage, I would ride with them," said the Rev. Gregory Daniels, organizer of the Chicago event, taking a far more provocative stance than the vast majority of black — or white — clergy members speaking out on the issue.
The National Black Justice Coalition, which was planning public events with black religious and civic leaders for the spring as well as an advertising campaign in black media outlets to make a case for gay marriage, is scrambling to put together a more immediate response.
"We thought we had a few months to organize," said Keith Boykin, president of the organization, which formed in December to respond to what its members said was a dangerously one-sided airing of black public opinion on the issue. "Now we have to think in terms of days. We have to step it up."
Many important players on each side of the debate already have backing from black churches. The Alliance for Marriage, the multifaith, multiethnic coalition that oversaw the drafting of the text for the constitutional amendment now before Congress, includes among its founders bishops from the African Methodist Episcopal Church and the Church of God in Christ, two historically black denominations.
The Coalition on Urban Renewal and Education, a Los Angeles-based conservative organization that works with black religious and community groups on social policy issues like school choice, arranged Ms. Wood's talk as well as meetings of clergy members with the Heritage Foundation and the White House.
In Boston three black clergy organizations — the Black Ministerial Alliance, the Boston Ten-Point Coalition and the Cambridge Black Pastors Conference — issued a joint statement against gay marriage in early February, drawing a swift rebuke from pastors supporting the unions.
At the heart of the conflict, for many, is not merely theology, but the mantle of civil rights.
"There has always been this undercurrent, from the women's movement through other movements, that the history of black people and their struggle was being opportunistically appropriated by an assortment of groups when it was convenient," said the Rev. Gene Rivers, president of the National Ten-Point Leadership Foundation, a church-based violence-prevention program. "This movement is particularly offensive because it hits at the Book, the Bible, and the painful history of black people all at once."
Blacks fighting to establish same-sex marriage are pushing their allies to be more vocal.
"Yes, this is different from back-of-the bus and Jim Crow," said Ms. Payne, who is a lesbian and a churchgoer. "But it's discrimination all the same. And when we make that case to black people, they understand."
The National Black Justice Coalition Web site lists prominent supporters including the Rev. Peter Gomes, chaplain at Harvard, the Rev. Al Sharpton, Democratic presidential candidate, and Coretta Scott King, widow of the Rev. Dr. Martin Luther King Jr.
Perhaps trying to appease both sides, the Rev. Jesse Jackson remarked briefly on the issue in a recent speech at Harvard Law School, saying that he supported "equal protection under the law" for gays. But he added that he viewed comparisons to the historical struggles of blacks as "a stretch."
"Gays were never called three-fifths human in the Constitution," he said, "They did not require the Voting Rights Act to have the right to vote."
In other remarks in Boston, Mr. Jackson vowed that Republicans would not succeed in making the debate a wedge issue in the presidential race. Some black pastors enmeshed in the issue agree.
"Ultimately black churches cannot be dictated to on this from the left, right or center," said Mr. Rivers, a Democrat who has advised President Bush on religion-based social services and who supports some benefits for same-sex couples. "Most of the same people who believe fundamentally that marriage is between a man and a woman and who will stand up and support that with conservatives voted for Al Gore in 2000 and oppose tax cuts for the rich and cutting social services in 2004."
Still others said the most significant outcome of the political ruckus could be the start of meaningful discussion in black churches, many of which have been historically resistant to tackling any topics dealing with sexuality, including H.I.V./AIDS and births out of wedlock.
"Often this kind of dialogue in black churches lags behind social debate," said Dr. Robert M. Franklin, an ethics professor at Candler School of Theology at Emory University, in Atlanta. "The value-added dimension of the political gamesmanship is that it will accelerate a much-needed conversation."