On a day usually given over to reflection and introspection, millions of Americans attended church services Sunday that galvanized them politically and underscored the nation's divisions on the eve of a bitterly contested presidential election.

From pulpits across the country, there were denunciations of abortion, criticisms of the war in Iraq and -- above all -- reminders to vote Tuesday.

Most church officials stopped short of endorsing President Bush or Sen. John F. Kerry, mindful that such activism could endanger their congregation's tax-exempt status.

Sunday's spiritual rhetoric was especially heated in the so-called swing states, which experts believe hold the key to electoral victory.

In Grove City, Ohio, parishioners at the Church of the Nazarene, a 5,000-member evangelical church near Columbus, found a Christian Coalition voter guide inside their weekly service leaflet. It said: "This voter guide is provided for educational purposes only and is not to be construed as an endorsement of any candidate or party."

Nor did the senior pastor of the church, Bob Huffaker, mention any particular names when he asked church members to bow their heads in prayer: "Father, as we walk into those booths, we pray your holy spirit would go with us and we would make the right decisions," he said. "You already know the outcome of this. We don't."

Huffaker said later there was little doubt that the vast majority of his parishioners would be casting their ballots for Bush.

At Divine Mercy Catholic Church in South Milwaukee, Wis., a blue-collar community targeted by both candidates, Father Bob Betz used the church bulletin, not the pulpit, to get out his message urging parishioners to vote.

While Betz preached at the morning Mass, a parishioner put a "Voter's Guide for Serious Catholics" on windshields in the parking lot. The guide, published by the San Diego-based advocacy group Catholic Answers, did not name either candidate, but it clearly delivered an anti-Kerry message.

It listed five "nonnegotiable" issues "that are intrinsically evil and must never be promoted by the law": abortion, euthanasia, embryonic stem cell research, human cloning and "homosexual marriage."

There was a different message in Houston at the New Mount Calvary Baptist Church, a working-class, primarily African American congregation of about 300. The theme for the morning service was "Red, White and Blue for Democracy."

"We are at a crucial time in our nation's history," Assistant Pastor Walter Gibson told the congregation to a chorus of "Amens." "There are many people who are unemployed, many without health insurance.... This Tuesday we have a chance to do our part as responsible citizens of this nation, to vote and let our voice be heard."

Gibson asked if there was anyone present who was old enough to have faced obstacles when they tried to vote during the civil rights era. A few men and women stood.

"We want to say thank you for all you went through so that we can let our voice be heard on Tuesday," Gibson said as the congregation stood and cheered. "We're going through all kinds of difficulties in this nation, but if we stand together we can hang on in there."

Pastor Willie Jones suggested Bush's faith didn't outweigh the problems of his presidency. He began to list the problems, beginning with unemployment, the national debt and Iraq before stopping himself.

"It just goes on and on," he said in an interview. "Bush acts like he's a gunslinger from Texas, when what we need is a leader who is cool and even-tempered, like Kerry."

In California, sermons rallied believers on both sides.

At All Saints Church in Pasadena, a liberal Episcopal congregation of 3,500 members, Rector Emeritus George Regas began by telling congregants: "I don't intend to tell you how to vote. We can just agree to disagree. You go your way and I'll go God's way," he said, provoking laughter from the crowd.

Then Regas delivered a searing indictment of the Bush administration's policies in Iraq. He criticized the drive to develop more nuclear weapons, and described tax cuts, which he said benefited the rich, as inimical to the values of Jesus.