Some black clergy see no good presidential choice between a Mormon candidate and one who supports gay marriage, so they are telling their flocks to stay home on Election Day. That’s a worrisome message for the nation’s first African-American president, who can’t afford to lose any voters from his base during a tight race.

The pastors say their congregants are asking how a true Christian could back same-sex marriage, as President Barack Obama did in May. As for Republican Mitt Romney, the first Mormon nominee from a major party, congregants are questioning the theology of the Church of Jesus Christ of Latter-day Saints and its former ban on men of African descent in the priesthood.

In 2008, Obama won 95 percent of black voters and is likely to get an overwhelming majority again. But any loss of votes would sting.

“When President Obama made the public statement on gay marriage, I think it put a question in our minds as to what direction he’s taking the nation,” said the Rev. A.R. Bernard, founder of the predominantly African-American Christian Cultural Center in New York. Bernard, whose endorsement is much sought after in New York and beyond, voted for Obama in 2008. He said he’s unsure how he’ll vote this year.

It’s unclear just how widespread the sentiment is that African-American Christians would be better off not voting at all. Many pastors have said that, despite their misgivings about the candidates, blacks have fought too hard for the vote to ever stay away from the polls.

Black church leaders have begun get-out-the-vote efforts on a wide range of issues, including the proliferation of state laws requiring photo identification cards to vote, which critics say discriminate against minorities. Last Easter Sunday, a month before Obama’s gay marriage announcement, the Rev. Jamal-Harrison Bryant of Baltimore formed the Empowerment Network, a national coalition of about 30 denominations working to register congregants and provide them with background on health care, the economy, education and other policy issues.

Yet, Bryant last month told The Washington Informer, an African-American newsweekly, “This is the first time in black church history that I’m aware of that black pastors have encouraged their parishioners not to vote.” Bryant, who opposes gay marriage, said the president’s position on marriage is “at the heart” of the problem.

Bryant was traveling and could not be reached for additional comment, his spokeswoman said.

The circumstances of the 2012 campaign have led to complex conversations about faith, politics and voting.

The Rev. George Nelson Jr., senior pastor of Grace Fellowship Baptist Church in Brenham, Texas, participated in a conference call with other African-American pastors the day after Obama’s announcement during which the ministers resolved to oppose gay marriage. Nelson said Obama’s statement had caused a “storm” in the African-American community.

Still, he said “I would never vote for a man like Romney,” because Nelson has been taught in the Southern Baptist Convention that Mormonism is a cult.

As recently as the 2008 Republican primaries, the SBC’s Baptist Press ran articles calling the LDS church a cult. This year, however, prominent Southern Baptists have discouraged use of the term when addressing theological differences with Mormonism. Many Southern Baptist leaders have emphasized there are no religious obstacles to voting for a Mormon.

Nelson planned to vote and has told others to do the same. He declined to say which candidate he would support.

“Because of those that made sacrifices in days gone by and some greater than others with their lives. It would be totally foolish for me to mention staying away from the polls,” he said in an email exchange.

Romney has pledged to uphold conservative positions on social issues, including opposing abortion and gay marriage. But many black pastors worry about his Mormon beliefs. Christians generally do not see Mormonism as part of historic Christianity, although Mormons do.