They were only modest dreams that led Wendel Pereira to leave his family and country just before Christmas. He promised to return in three years with enough money to marry his fiancee and buy a house and maybe a car.

His first ride on an airplane, to Mexico, went fine. Wading across the cold Rio Grande into Texas was manageable. Two weeks after slipping into the United States, however, the 23-year-old Brazilian was dead of an apparent asthma attack, his body destined for a pauper's burial.

His fate made news here in his home town. But it has not halted the growing number of Brazilians trying to enter the United States illegally, an upsurge over the last year that has caught authorities by surprise.

Driven by unemployment, increasingly sophisticated smuggling rings and even, some say, a wildly popular soap opera about Brazilian immigrants in the United States, the number of people from Latin America's most populous nation attempting to sneak into the land of opportunity up north appears to be hitting levels not seen in years, if ever, officials in both countries say.

They cite the steep climb in the number of Brazilians arrested at the U.S.-Mexico frontier, the main point of entry. For the year ending last Sept. 30, U.S. authorities detained about 8,900 Brazilians trying to cross the border, mostly into Arizona or Texas. Since then, with three months remaining before the end of the current fiscal year, that figure has nearly tripled, to more than 25,600 detentions.

Excluding Mexico, by far the largest source of illegal immigrants, Brazil ranks behind only Honduras in the number of nationals apprehended at the southwestern border, having surpassed El Salvador on the strength of the recent wave, according to U.S. government statistics. If present trends continue, this nation with a population of about 186 million, many mired in poverty, could eventually eclipse Honduras.

"The numbers are staggering," said a U.S. official who works on the issue, speaking on condition of anonymity. The numbers suggest there is more going on than stepped-up enforcement, he said. And, of course, they represent only the Brazilians who get caught.

Authorities are hard-pressed to identify an overriding reason for the increase from a year ago. But they note that illegal immigration from Brazil had been on the upswing in previous years and that economic prospects remain bleak for many in this country. The Brazilian National Congress has established a committee to investigate the issue.

In part, the United States blames the influx on Mexico, which stopped requiring visas of visiting Brazilians in 2000. That has facilitated a rush north, as planeloads of Brazilians touch down in Mexico City and many passengers, passports in hand, sail through customs and head for the border.

Washington has pressured the Mexican government to scrap its visa-free policy, a change that was expected in May. But a spokesman for the Mexican Embassy in Brasilia, the Brazilian capital, said there was no confirmed date for visa applications to resume.

"We would cut [the influx of Brazilians] down by 50 percent, easily, probably more than that," if Mexico reinstituted its visa requirement, the U.S. official said.

The would-be immigrants hail from throughout this vast country, including the wealthier south. But the nerve center of the human traffic remains here in the eastern state of Minas Gerais, which has had connections to the United States for half a century.

In a reverse image of the present situation, Americans began flocking to this area after World War II to help build a railway and to mine the region's minerals, metals and gemstones.

Historians say many of these Americans brought Brazilian wives and maids home with them, which triggered a northward stream of immigrants as the women invited relatives to join them. Within a few decades, Brazilian enclaves were well-established in the United States, and striking out for America became a part of life in Minas Gerais.

"There was no intention to stimulate immigration, but the development of support networks for the pioneers who left in the '60s and, on a greater scale, in the '80s, led to this," said Ana Cristina Braga Martes, a sociologist.

Signs of American influence abound in Governador Valadares, a city so well-known for exporting sons and daughters and benefiting from the money they send home that a resident once called the United States "the cradle of Valadares civilization."

People flock to a nightclub called America, motorists often carry U.S. driver's licenses, and Western Union plays a major role in the life of the community.

"All the pretty houses are built with money from America," said Gilson da Silva, a cabdriver who has a sister and a cousin living in the Boston area.

The constant hammer-and-saw medley of new homes being erected with money from the United States acts as a powerful advertisement for emigrating, especially to young people glum about their opportunities in Brazil.

So does "America," a nightly soap opera about Brazilian immigrants in the United States. Although the idea of viewers uprooting themselves and moving to a foreign country because of a television show might sound far-fetched, such programs have a great hold on the public imagination here. Rui Antonio da Silva, a federal police officer, said he thought there was a connection, adding that scenes of hardship on the show don't outweigh the tantalizing depictions of success.

"Brazilians have a spirit of adventurism and self-sacrifice, so a little suffering is no big deal," he said. "There was a time in the '60s when parents in the northeast would pat their kids on the head and say, 'Grow up and go to Sao Paulo,' " he added, referring to Brazil's industrial center. "Here in this region, the parents pat their kids on the head and say, 'Grow up and go to the United States.' "