Mexico’s increasingly destitute poor are turning to what the U.S. military calls a “death cult” for comfort.

The barrio of Tepito, where it’s said that everything is for sale except dignity, has been one of Mexico City’s roughest neighborhoods since Aztec times. Famous for its black market and its boxing champions, Tepito is a place where residents learn to fight early and fight hard. These days it has also become the epicenter of Mexico’s fastest-growing faith: Santa Muerte, or Holy Death, a hybrid religion that merges Catholic symbolism with pre-Hispanic worship of the skeletal Mictlantecuhtli and Mictlancihuatl, Lord and Lady of the Dead.

I recently went there for an outdoor mass at one of Santa Muerte’s first public shrines, founded eight years ago by a great-grandmother named Enriqueta Romero. When I visited in November, Romero placed a necklace with skull pendant around my neck as some 5,000 worshippers surged toward the glass-encased skeleton outside her house. Clad in a faded housedress, she told me that Mexico’s Catholic churches stand empty while thousands of Holy Death shrines have spread across the country because “the church reprimands,” but Santa Muerte never does. “She accepts everyone, with faults and without.”

Ex-convicts attest to Santa Muerte’s help in springing them from prison, while other devotees beseech her for help with jobs, illnesses, a pregnant daughter, a drug-addicted child. Taxi drivers and prostitutes plead for protection, as do soldiers and police. A gaunt blonde in skintight jeans and pancake makeup places a candle beside Romero’s shrine, while a transgender woman clutches her personal altar like a child. Worshippers bring gifts — candy, cigarettes, tequila, flowers, fake paper money — to the little temporary shrines that line the sidewalks around Romero’s house like a flea market. Some anoint the skeleton with mescal; others hold joints to her bony lips.

The worship of Santa Muerte, first noted among Mexico’s poor in the middle of the last century, remained a largely underground practice until the last decade; since then, it has become a full-fledged mainstream cult with 2 million to 5 million followers, practiced in an increasingly public fashion both in Mexico and the United States. Its rise has provoked alarmist rhetoric. A U.S. military report brands Santa Muerte “the death cult of the drug lords,” and indeed her shrines are frequently uncovered during police raids on narcos on both sides of the border. In March 2009, the Mexican Army bulldozed some three dozen shrines near the U.S. border as part of a psychological war on “narcoculture.”

But the drug war is only tangentially connected to Santa Muerte: “Her primary base is poor people — those excluded from the formal economy or who have lost faith in the judicial system,” says Lois Ann Lorentzen, director of the University of San Francisco’s Center for Latino Studies in the Americas. Santa Muerte’s popularity, rooted in dangerous urban areas like Tepito and the rural regions that increasingly resemble them, reflects economic and political uncertainty in a country where almost 50 million people live below the poverty line.

The faith’s recent growth coincides with developments that have disproportionately affected its already marginalized followers. The world financial crisis hit Mexico harder than most other countries due to its reliance on U.S. trade; the economy shrank 7.3 percent in 2009, its worst year since 1932. Even before that, many border factories producing goods for U.S. companies had relocated to China, and the livelihoods of millions of peasants were undermined by the 2008 elimination of farm tariffs under the North American Free Trade Agreement. The worldwide downturn has affected Mexican migrants as well, with remittances to Mexico dropping 15 percent last year.

At the same time, Mexico’s drug war has taken a turn toward ultraviolence, with more than 15,000 killed since President Felipe Calderón declared war on the cartels following his disputed 2006 election. While the rich armor their cars, hire bodyguards, and implant microchips so they can be traced in a kidnapping, the poor have no such options. “People are asking Santa Muerte for protection,” says filmmaker Eva Aridjis, who made a documentary about the cult, “protection against herself really, against death.”

For historian Ronald Wright, the cult’s growth is a specifically Mexican response to the country’s woes. While people in other developing countries facing similar pressures, such as Colombia or poor areas of the Middle East, have turned to fundamentalist forms of Christianity or Islam in response, Mexico is drawing largely on elements from its own culture. “Mexico’s poor feel abandoned,” he told me. “Elsewhere in the world, people who feel marginalized are turning to fundamentalisms, but Mexico’s poor are drawing on ancient traditions to reconstruct an identity that helps them survive.”

Despite Santa Muerte’s dark reputation, the Tepito mass, held on the first Sunday of each month, has a carnival atmosphere. Mariachi bands play next to the shrine. A pretty nurse brings her young niece to pray for a sick relative while shirtless street toughs drink beer and show off the Santa Muerte tattoos on their chiseled chests. “It is not safe to wander around,” says Luis Martinez, a burly member of Enriqueta Romero’s family who pronounces himself my bodyguard at her behest. A vendor of pirated DVDs, Martinez shows me his tattoo of Christ wearing a crown of thorns. Like most devotees, he sees no contradiction between Catholicism and Holy Death: The Catholic Church still claims around 90 percent of Mexicans as members, though recent battles over same-sex marriage and abortion suggest its influence might be on the wane.

In the case of Santa Muerte, the church pronounces the cult heretical, the religion of criminals. Yet efforts to combat drug trafficking by destroying shrines are rather like bulldozing tattoo parlors to get rid of biker gangs. Such tactics may well engender a backlash: In the wake of last year’s crackdown, hundreds of Holy Death followers marched in the main square of Mexico City chanting, “We are believers; we are not criminals.”

As the mass begins, Romero invites me onstage next to her shrine. Silence falls over a crowd that stretches as far as I can see. Men and women, young and very old, eyes closed or raised to the sky, they listen intently as a man with a microphone pleads with the “White Girl,” the “Holiest Death,” to bring succor to those in need. Even the children pay attention. There is earnest devotion, tears, and a sense that here at last is someone who listens. If anything threatens the national security of Mexico, it is not the religious beliefs of the poor, but the political and economic despair that draws them here.