RIO DE JANEIRO — The Carnival band kicked off according to tradition: Dozens of percussionists struck their bass drums, sending a low rumble like a sustained thunderclap echoing among the skyscrapers of Rio's downtown. Tambourines answered lightly, tinkling over the drummers' resounding call. Dancers responded with a roar, throwing up their hands, feet leaping to the frenetic beat.

For years, the samba's staccato rhythm has been the backdrop for songs celebrating the debauchery that marks this city's five-day street party. This time, however, the lyrics came with a surprising twist.

"We are the people of the Lord, a holy nation," the revelers sang. "We are here to proclaim the marvels of he who has called us from the darkest depths to his glorious light, and to glorify the name of Jesus."

The chorus, "Oh, Jesus!" and the 5-foot-tall letters spelling out "Jesus (heart) you" on top of the float bearing loudspeakers left little doubt of the band's intentions: to evangelize through samba, using Rio's Carnival extravaganza to fish out souls in greatest need of conversion.

"We're here for those who are lost, without hope, hungry for God," said Isabel Gutierrez, a member of the Mocidade Dependente de Deus band, whose name loosely translates as "Youth that Depends on God."

"We used to go on retreat during Carnival, but doing that we don't save anyone," she said. "We're here to spread the real good news."

Brazil's Carnival may have religious roots: It is an exaltation of the pleasures of the body, before the deprivation of Catholic Lent. Its modern expression, however, is undeniably secular, with partiers so focused on finding the next street band or beer vendor that every year's festivities overshoot Ash Wednesday, when tradition says sobriety should settle in.

Resolutely pushing against that tide of hedonism are a few "blocos," or roving street bands, such as Mocidade Dependente de Deus. It is one of at least three Christian Carnival bands that try to use the yearly party to do some "strategic evangelizing.

The tactic works, said participants who called the experience exhilarating, because it ushers them to the front lines of a spiritual battlefield.

"I've seen people accept Jesus during Carnival because they heard us and felt the call," said Luciana dos Santos Silva, who has been parading with Mocidade for three years. "Lives are saved here."

Skeptics eyeballing Mocidade's offer of Bible verses over beer and salvation over easy flirtation were amazed that the sober and modest parade was getting attention when all over town, more traditional Carnival bands offered the usual mix of heady sensuality and booze-fueled mayhem.

Stripped down to shorts and grimy flip-flops after a sweaty morning of dancing in the streets, Pedro de Alcantara Soares, 24, sipped a beer and cast a critical glance at Mocidade while waiting for the next band.

"It's up to them to convince us," he said. "They have a lot of work to do."

Church leaders say the growing number of parade followers is evidence that their efforts have been a success.

Mocidade was founded in 1988 as a church band with a handful of participants, and now has about 2,500 active members. The other evangelical Christian band with a significant following, Cara de Leao, or Lion's Face, was established in the early 1990s as a bloco and counts on 5,000 organized participants.

During the past few years, they've grown from church bands into Carnival blocos with a real following, their popularity exploding along with the number of Brazilian Protestants. Thirty years ago, almost 90 percent of the population said it was Catholic. Now about 20 percent identify with a Protestant church, many of which were founded by American evangelicals.

Brazilians, staggering under hyperinflation and other economic woes, flocked to the churches in the 1990s, and the neo-Pentecostal movement became a social and cultural force, with members running for elected office, buying up television channels and overseeing arena-sized churches focused on nuts-and-bolts self-improvement as well as ministry.

While the numbers of neo-Pentecostals have stabilized, they continue to exert a powerful influence, shaping public discourse though politics and flashy strategies such as the Carnival blocos.

A Catholic Carnival band, whose name loosely translates as "Party with Christ," started about five years ago. It counted on the star power of Rio's Archbishop, Orani Tempesta, to attract 50,000 people to this year's parade two weeks before Carnival, according to church estimates. Tempesta's mass kicked off a celebration that went on to include singing and dancing to rival any secular Carnival celebration.

"Each year the number of participants grows, which proves that Party with Christ is an event that's here to stay," organizing priest Renato Martins said in a statement.

The church leader in charge of Lion's Face, Marcos Campos, said in a statement that putting out a Christian message in the heart of downtown, in the middle of the city's most heathen celebration, was an inspiration, although the public didn't always agree.

Some drunken onlookers had become a little too aggressive in taunting church members, he said. So the congregation started sending members to the area before the band's arrival, to preach the gospel to unaware partiers — arguably giving those not interested in the Lord some time to leave and continue their pursuit of earthly pleasures elsewhere.

"Now we enter the territory of the enemy after destroying its fortress. The results have been good. When the band arrives, people are ready to participate in prayer," Campos said in a statement.

Still, church members surround the parade to create a buffer and hand out pamphlets with Biblical verse.

The church behind Mocidade, based in Rio's wealthy south side, has been hosting nightly prayer meetings during Carnival to help the faithful resist the temptations elsewhere. Its band parades twice, downtown and along the waterfront, competing with decidedly irreligious bands with suggestive names such as Cheap Thrill, Last Call and Dear, I'll Be Right Back.

Monday's parade drew a few hundred onlookers outside the church's own congregation in a markedly sober event. Participants donned T-shirts proclaiming their love of Christ, in sharp contrast to the minimalist approach to clothing that marks secular parades. Even the city's ubiquitous beer vendors, a fixture in any crowd, were scarce.

Still, many of the onlookers welcomed the band, staying true to Carnival's all-inclusive spirit.

"Enthusiasm doesn't discriminate: They can have their fun, too," said Lylian Arides, trying to stay cool in a tank top, shorts and flower lei, sipping a beer with friends as the band paraded by. "Even if their message isn't for you, the music's good."