The result, in the short term, could be a boost for the centrist candidacy of former New York City Mayor Rudolph W. Giuliani, whose messy personal life and support for gay rights and legal abortion have not produced the unified opposition from Christian conservatives that many anticipated.
Over the longer term, the distancing of religious leaders from politics could prove even more consequential, denying the GOP one of the essential building blocks it has used to capture the White House in five of the last seven presidential races.
The shift is evident in this Rocky Mountain community at the heart of the evangelical movement.
"As far as me standing in the pulpit holding a voter guide, that's not going to happen," said the Rev. Brady Boyd, 40, who leads a congregation of 10,000 at New Life Church. He will use his position to teach the Bible to believers. "I won't use it to influence their vote," he said.
That suits many in his congregation just fine. "If he starts talking politics, that makes me very uneasy," said Wolfgang Griesinger, 56, a political independent.
"It's not his place to tell us who to vote for," said Marsha Thorson, 54, a Republican who is leaning toward Giuliani.
Black churches have a long tradition of political activism, mostly on the Democratic side. White evangelical churches did not assert themselves politically until Ronald Reagan's 1980 campaign, when first the Moral Majority and later the Christian Coalition began organizing on behalf of Republicans.
The term "evangelical" refers to Christians who claim a personal relationship with Christ and consider the Bible the word of God, to be faithfully obeyed. They are a huge group -- about one in four voters -- and far from monolithic; their ranks include Pentecostals, charismatics, Southern Baptists and many others. Some worship to rock music, others to hymns; some speak in tongues. Some believe God preordained those headed to heaven; others hold that anyone can achieve salvation by accepting Jesus Christ as their savior. Former Presidents Carter and Clinton are evangelicals, as is President Bush.
Despite that diversity, evangelicals have become a reliable -- and increasingly crucial -- Republican voting bloc. Many were drawn to Bush in 2000 because of his conservative stance on social issues and his story of turning to Christ to overcome a drinking problem. He won the support of more than eight in 10 Christian conservatives in 2000 and nearly nine of 10 in 2004, according to Los Angeles Times exit polls.
But in the three years since, many Christian conservatives have expressed a growing unease about the entanglement of politics and pulpit. Among young evangelical adults, nearly half say involvement in politics is problematic, according to a new book, "unChristian," from the evangelical research firm the Barna Group.
Some of that disillusionment comes from disappointment with Bush's policies, including the war in Iraq. But there's also shame at the often-bombastic, sharply partisan rhetoric of the traditional standard-bearers for conservative Christian values, including televangelist Pat Robertson, 77; the Rev. Jerry Falwell, who died this spring at age 73; and radio host James C. Dobson, 71.
One-third of evangelicals under 30 told Barna that they were embarrassed to call themselves believers.
"They're tired of the hard-edged politics that the Christian right has practiced in the last couple of generations," said John C. Green, senior fellow at the Pew Forum on Religion & Public Life. "They see all this division, all this anger, without a lot to show for it."
Mega-church pastors have capitalized on that frustration by offering a different brand of Christianity. With sunny, affirming services, they cast a broad welcome net -- and fill arena-size sanctuaries each Sunday.
They may promote a cause, such as AIDS relief in Africa. But endorse a candidate? Push a partisan agenda? That could empty half their pews. Few up-and-coming pastors want to risk such a backlash.
"There's nothing in it for them," said Timothy Morgan, deputy managing editor of the evangelical monthly Christianity Today. "It just gets people stirred up."
Florida pastor Troy Gramling, 40, recently preached a series he called "My Naked Pastor," which involved airing his every thought to webcams that followed him around the clock. Make that almost every thought: Gramling said he would never announce to his congregation of 14,000 how he planned to vote.
"That would be putting pressure on them to agree with me, and I don't feel I have a right to do that," Gramling said. "God doesn't call me and tell me who's his favorite."