In 1963 the Rev. Martin Luther King Jr. famously said, "At 11 on Sunday morning when we stand and sing and Christ has no east or west, we stand at the most segregated hour in this nation."

Forty-five years after his indictment of U.S. Christendom, and eight days before a racially historic presidential election, there is a new, troubling undercurrent in some of America's strongest, most integrated churches.

Many major cities can now boast of churches large and small where the unself-conscious array of skin colors, the joyful mix of musical styles and the unity of fellowship would thrill Dr. King's heart.

And the integration is not a cosmetic, Sunday morning-only gesture. While the mighty Brooklyn Tabernacle, a veritable United Nations of the gospel, draws its 10,000 members from the New York area's diverse millions, integrated churches in the more racially and ethnically segregated city of Pittsburgh -- such as Allegheny Center Alliance Church and New Hope Church on the North Side and Covenant Church of Pittsburgh to the east -- are changing where and how their members live.

Behind this migration is a belief: Racial reconciliation is a daily commitment. Living as equals before God may require whites returning from suburbs to city and willingly shouldering burdens that disproportionately weigh on African-American lives.

But in the waning days of a racially charged election, some white Christians who have lived and ministered shoulder to shoulder with black Christians for years are speaking with frustration about the political gauntlet being thrown at their feet.

"For the first time in my life my [spiritual] commitment is being questioned," said one white woman deeply involved in an integrated Pittsburgh ministry for years. I'd called her for a different story and was surprised to stumble into her anguish.

She's a free-market, pro-life conservative unable to support Barack Obama because of his position on such issues. "The expectation that I should restructure my lifelong political convictions to prove something [on race] -- that's the most bigoted thing ever!"

If the point of their joint life's work is that faith transcends race, how can her black co-believers now apply a racial litmus test to her Christian ministry?

She sees white evangelicals pulling back. "Go to a church that's more white and drive through the parking lot," she said. "You'll see McCain and Obama bumper stickers both. But if you go to an integrated church, you won't find McCain stickers. It's a very conscious choice that's occurring."

Another white evangelical at a different integrated church echoed that theme, noting that only Obama supporters wear their buttons into services. "On principle I'd love to vote for a black president, but I can't vote for Obama for so many reasons," she said, mentioning abortion in particular. "As a conservative, I don't bring things up. The relationships are more important to me than the politics."

Perhaps for that reason, few of the people I contacted -- black and white, ordained and laic -- were willing to talk, even with the protection of anonymity.

One who would is the Rev. Dr. Rodger Woodworth, who founded New Hope Church in the distressed Marshall-Shadeland neighborhood in 1994. "We try to keep politics out of the pulpit," he said, but he noted that the danger of making assumptions can cut two ways. He's received -- and rebuffed -- "strongly worded e-mails from white suburban evangelicals" who assume he shares their political agenda.

In fact, white evangelical Christians have been trending Republican for 20 years, and in 2004, George Bush won 59 percent of all Protestant voters and 78 percent of evangelicals. But this year, the presence of a black Christian on the Democratic ticket complicates decisions -- or relationships -- for some.

"I'm really conflicted," Dr. Woodworth said. "I've felt people pull back just a hair at realizing I might be considering Obama."

Despite 30 years living and working in inner cities, he said, "I can't put myself in a black person's shoes: To finally see a candidate of their race who has so many good characteristics -- whether we agree with his politics or not -- and not feel some identification or favoritism? ... I never have to go through my day in black skin, so I always fall short of understanding."

He, however, would go into the fray. "Sometimes we whites are too careful, tiptoeing around. I'd say, 'Help me understand this.' "

Being truly reconciled, he said, takes time and requires the willingness to listen to the other person's pain. "We can be reconciled," he said, "even if we can't resolve the differences we have."

Indeed, one lay person noted, the differences we have will survive Election Day. "Whoever wins this isn't going to solve the issues we face. Whoever wins this, we still have the same calling. It's Jesus in our lives that will heal the divide."