And many evangelicals are interested in far more than the hot-button issues of abortion and homosexual marriage often used to define them. Evangelicals have been active in seeking increased aid for Africa, fighting poverty, battling the traffic in sex slaves, and supporting efforts to reduce global warming.

Evangelicals are not just Pat Robertson and Jerry Falwell and George W. Bush. They are also Jimmy Carter and Bill Clinton and the Rev. Dr. Martin Luther King Jr.

And Haggard. And the Rev. Rick Warren, the California preacher who wrote The Purpose Driven Life, which has sold 23 million copies since 2002. And Ron Sider, founder of Evangelicals for Social Action in Wynnewood.

"Evangelical does not mean any specific political ideology," said Haggard, a conservative who talks regularly with President Bush and met earlier this month in Washington with British Prime Minister Tony Blair.

"I think the power base is shifting," said Haggard, who sees a new generation of leaders less bombastic and more socially active than televangelists such as Falwell and Robertson. "We think differently than the previous generation, the 1980s Moral Majority crowd."

Most Americans consider religion an important part of their lives (83 percent say it is "very" or "fairly" important). But there is no consensus, even among evangelicals, on how to translate faith into action.

"The vast majority in the evangelical center are regularly embarrassed by what Jerry Falwell or Pat Robertson say, but they don't go around issuing press releases attacking them," said Sider, author of Rich Christians in an Age of Hunger.

The National Association of Evangelicals, which represents 30 million evangelicals, last year adopted a new manifesto for social engagement, For the Health of the Nation: An Evangelical Call to Civic Responsibility, cowritten by Sider. In it, the group spells out a broad agenda: "To protect the vulnerable and poor, to guard the sanctity of human life, to further racial reconciliation and justice, to renew the family, to care for creation, and to promote justice, freedom and peace."

"God measures societies by how they treat the people at the bottom," the document states.

Broadly defined, evangelicals are Christians who have had a personal or "born-again" religious conversion, believe the Bible is the word of God, and believe in spreading their faith. (The term comes from Greek; to "evangelize" means to preach the gospel.) The term is typically applied to Protestants.

Millions of Americans fit the definition, although estimates vary on exactly how many. Forty-two percent of Americans described themselves as evangelical Christians in a Gallup poll in April, while 22 percent said they met all three measures in a Gallup survey in May. The National Association of Evangelicals says about 25 percent of adult Americans are evangelicals. Larry Eskridge, associate director of the Institute for the Study of American Evangelicals at Wheaton College, puts the figure about 33 percent.

"If you're talking about 33 percent of the population, they're not this 'other.' They're your next-door neighbor," Eskridge said.

And, like many neighbors, evangelicals can be maddeningly difficult to categorize.

They are Methodists, Presbyterians, Episcopalians and other mainline Protestants, as well as Southern Baptists and members of nondenominational mega-churches. Without a uniform theology, they vary widely in interpretations of the Bible and its application to their lives and nation.

With these and other strands of evangelical Christianity, "sometimes the most visible and those who shout the loudest are considered the core," said Bishop C. Milton Grannum, minister of New Covenant Church of Philadelphia, most of whose 3,000 members are African American. "But there are thousands of African American and Hispanic churches that are evangelical, and they should not feel threatened by the fact that they are not as visible."

Black evangelicals are often "charismatics," a trait shared with Pentecostals and many other evangelicals. Charismatics believe the active influence of the Holy Spirit is evident in such practices as faith healing and speaking in tongues.

Despite a common ground of Scripture and tradition, various evangelical congregations often inhabit parallel universes, with different priorities, experiences and politics.

"There's a difference in the way we identify politically because there is a difference in the way we identify, period," said Grannum of black evangelicals. "We have had totally different experiences... . The church reflects the larger community."

Edmund Gibbs, a professor at Fuller Theological Seminary in Pasadena, Calif., said the popularity of right-wing politics is overstated.

"Many of us who consider ourselves to be evangelical Christians would want to distance ourselves from that kind of alignment," said Gibbs, an Episcopalian. "And it is very much an American thing; most evangelicals in Europe would distance themselves from the politics associated with evangelicals in the United States."

Haggard said his mission is to broaden the movement's base and its vision.

"My role is to help the various members of the body to respect each other and work together... to make life better for everybody."

Many Faces of Evangelicalism

Fundamentalists: They reject the theory of evolution, believe in the literal accuracy of the Bible, regard Catholics as non-Christians, and believe in separating themselves from the secular world. They do not seek to change the culture through legislation. The number of fundamentalists "is very small," said Jonathan Pait, spokesman for Bob Jones University, a fundamentalist college in Greenville, S.C. Larry Eskridge, associate director of the Institute for the Study of American Evangelicals at Wheaton College, estimates the number at "several million."

Traditionalists: They are characterized by efforts to maintain traditional beliefs and practices in the face of a changing society. Predominantly Republican (70 percent, compared with 10 percent independent and 20 percent Democrat), this group of white Protestants, with well-developed conservative political connections and ambitions, is closest to the popular notion of the "religious right." They represent about 12.6 percent of the population, or about 28 million adults, according to last year's National Survey of Religion and Politics by the Bliss Institute of the University of Akron.

Centrists and modernists: They are less tradition-oriented and more willing to adapt their beliefs and practices. They are more likely to identify themselves as Democrats or independents than as Republicans. They represent about 13.7 percent of the population, according to the Bliss survey, about 30 million people.

Black evangelicals: Most of the nation's 21 million black Protestants fit the evangelical definition, but their politics are the reverse of the white traditionalists: 71 percent identify themselves as Democrats and 11 percent as Republicans, according to the Bliss survey.

Hispanic evangelicals: Many of the six million Hispanic Protestants are converts from Catholicism, and they skew slightly toward Democratic politics.

Catholic evangelicals: This counterintuitive term identifies Roman Catholics who embrace much of the public-witness style of evangelical Protestants. "They have the fire and zeal usually associated with evangelicals," said William Portier, a religious studies professor at the University of Dayton and the author of the recent essay, "Here Come the Evangelical Catholics." Portier estimates the number of evangelical Catholics at 10 percent to 20 percent of the under-40 Catholic population.

END