La Paz, Bolivia -- It's Sunday morning in a rundown former cinema in the grittiest part of the Bolivian capital, and a 20-man brass band is thumping out a disco beat as line dancers onstage do an approximation of the Hustle.
"Who's living?" the bandleader in a powder-blue suit roars into his microphone.
A thunderous, ecstatic cheer rises from the thousands who pack the dilapidated hall: ''Je-SUS! Je-SUS! Je-SUS!"
The tunes are catchy, and worshipers dance as if at a party: Indigenous women in ponchos and petticoats twirl like giant tops, urban workers dance salsa and wave flags emblazoned with the words ''Power of God," and young mothers march in place and shake their babies to the rhythm.
The preacher calls a stream of parishioners onstage to testify that Jesus cured their tumors or tripled their crop output. After they gratefully hand over donation envelopes, he pours ''holy oil" on their scalps, and they yelp or shake with laughter and crumple to the floor, overcome by emotion. ''Let's give a hand to God!" the preacher's wife declares to encourage applause.
It's a far cry from the sedate Roman Mass at the nearest Catholic church, to which many of these faithful once belonged. These days, two-thirds of the pews there are vacant.
For newly installed Pope Benedict XVI, the pressing challenge in Latin America -- home to the greatest proportion of the world's Catholics -- will be to address the weaknesses in Catholicism that are fueling an exodus across this region.
Catholics are flocking to so-called ''health and wealth" evangelical sects, Mormonism, and other faiths that converts say better address their everyday concerns.
Protestantism is flourishing in a region that has been a bastion of Catholicism since the 16th century. In small towns, pastors are building communities of ''brothers" with door-to-door ministries to alcoholics, wife abusers, and the sickly. In large cities, charismatic preachers backed by electric keyboards promise deliverance from poverty through faith in Jesus.
The ranks of Protestant sects have doubled across the region over the past several decades, according to the Latin American Religious Studies Association.
"Religious conversion is the single greatest social process changing Latin America and the Caribbean in the 20th and 21st centuries," according to the Rev. Edward Cleary, director of Latin American studies at Providence College and a former Catholic missionary.
The most dramatic example is Guatemala, where 25 percent of the population is Protestant. The number of evangelicals is also increasing in Brazil, the world's most populous Catholic country, where 15 percent now call themselves Protestants, according to surveys. By some projections, Latin America will have a Protestant majority by the end of the century, according to David Reed, a theology professor at the University of Toronto.
Part of the flight may be explained by younger Protestant ministers and missionaries who can be more involved in their communities than older, overburdened Catholic priests.
In Mexico, home to the second-highest number of Catholics in the world, one priest serves 8,600 Catholics on average, according to church and census figures, while one evangelical pastor attends to 230 worshipers, according to Elio Masferrer, chairman of the Latin American Religious Studies Association. In the town of Potosi, Bolivia, there are 23 priests for 120,000 Catholics, according to the diocese, and 16 young Mormon missionaries who say they have attracted thousands of converts.
But many of the defections, according to interviews with converts here, stem from a view that the Catholic Church has not adequately addressed the gaping inequality, joblessness, and despair endemic to the region. To be sure, the church supports countless social service programs, but the disaffected say unmarried priests often seem removed from the daily concerns of the populations they serve. Many evangelical sects, in contrast, promise a more interactive worship service and worldly rewards through faith.
Here at the New Pact Power of God Church, about 10,000 Bolivians pack six shifts of worship led by charismatic preachers and aerobic musicians in a faded matinee hall every Sunday. Forty-five minutes into a three-hour service, the Good Samaritan band is going strong, and there has not been a single Gospel reading. When the preacher in a shiny charcoal suit and pink shirt comes onstage, he recounts the story of Jesus feeding thousands with a few fish and loaves of bread, and tells parishioners that they too can multiply their paltry resources through faith.
"Do you want to be blessed in the desert? Do you want to be cured?" the pastor bellows. ''Then take an envelope!" he urges, as ushers flap donation slips in the faces of middle-aged and older women, who reach out for them and scribble prayers on the envelopes to cure their ailments and find jobs for their sons.
"Eight years ago I joined this church because I was ill with a tumor. The pastor dunked me in water, and I gave my heart to God, who cured me," said Maria Mamani Vasquez, 55, a street vendor who gazed adoringly at Luis Guachalla, the sect's founder, who says he gave up hard living and began preaching in the streets of La Paz 22 years ago.
Ask around, and the stories of conversion are strikingly similar. Elvira Candari, a 35-year-old artisan, said she felt ''abandoned by the Catholic Church" during a painful divorce and was brought here by an aunt.
Justino Oacira Ramos, 74, an unemployed driver, said his wife brought him here to get him to stop drinking: ''The Catholic Church didn't really exist for me; they didn't help me." He did stop drinking.
Onstage, Magneli de Guachalla, the founder's wife and a self-taught preacher who says faith cured her kidney disease, engages the crowd with the skills of a motivational speaker and stand-up comedian. She recounts the tale of a desperate mother of five who went from sleeping in a mud hut to operating her own stores within six months of embracing Jesus.
Women who want to help their husbands and sons should mix a drop of holy oil in their eggs and pray, she advises.
A once-destitute cobbler now manufactures shoes because ''he's crazy about God!" she bellows. ''God will give you a house! If you think I'm materialistic, I am! Everything is possible with the power of God! Disbelief is a sin!"
Throughout the day, believers file onstage or upstairs to the church's low-budget national radio station to attest to death-defying miracles and financial rewards they have enjoyed thanks to faith and liberal use of holy oil. A hundred rustic crutches lie in the corner of the studio, testament to those who cast them off.
The clinking sound of coins donated toward the construction of a planned $2 million church is recorded behind their testimonials.
In a quiet interview between services, Guachalla, 43, says he had an instant conversion at age 21 when he met a Bolivian preacher who told him he had to stop drinking, smoking, and fighting with his wife. Explaining his church's appeal, Guachalla said simply, ''The Catholic Church doesn't have the answers."
Even many devout Catholics, such as Luis Bermejo, 37, a computer programmer who is an active member of the La Paz Cathedral, recognize the appeal of the sects: ''Their message is very human, to stop suffering. Evangelical churches are growing because people haven't found a way to solve their problems -- the lack of well-paid, dignified work, good education, and good healthcare -- and they don't see a response from the Catholic Church."
Cleary, from Providence College, notes that is not only the Catholic Church that is losing ground to ''health and wealth" neo-Pentecostal movements, but also mainstream Protestant churches.
Nevertheless, an overlooked aspect of conversion, he says, is the high dropout rate inside many of the new sects within a few years.
German Chambi, 42, pastor of the New Seed Mining Methodist Evangelical Church in Potosi, a mining town in southern Bolivia, says he does not fear losing the two dozen poor, indigenous members of his three-year-old church. They worship in a half-built concrete eyesore of an edifice, with a lone, off-key guitarist playing along, so Chambi reckons it is faith and not fireworks that bind his flock together.
Chambi, a third-generation Methodist minister, credits Methodists and Baptists with introducing education and land rights to Bolivian Indians such as his grandfather years before the state extended the right to vote and land reform to the indigenous majority in 1952. Even today, he asserts, Protestant churches are more sensitive to Indians than the mainline Catholic hierarchy.
"Our churches are more open, the songs use local rhythms, and I visit my people every day to check on their health and their family life," he said. ''Sure, Catholics have social services, but they hardly reach into the countryside and forgotten communities like this one."