By SIMON ROMERO

CARACAS, Venezuela, Dec. 3 — President Hugo Chávez was re-elected in a landslide on Sunday night, as voting tallies poured in from throughout the country. Mr. Chávez’s main opponent conceded defeat, paving the way for the president to begin a new six-year term.

With 78 percent of the votes counted, Mr. Chávez was ahead with 61 percent, compared with 38 percent for Manuel Rosales, the governor of Zulia State, Venezuela’s electoral council said late Sunday night as it declared Mr. Chávez the winner. Thousands of supporters filed into the streets around Miraflores, the presidential palace downtown, to hear Mr. Chávez deliver a victory speech in the rain.

“Long live the socialist revolution!” Mr. Chávez yelled to the crowd, pumping his fist in the air. His supporters, many of them dancing, reacted by chanting, “Ooh-ah, Chávez isn’t leaving!”

The win for Mr. Chávez gives him a stronger mandate to press forward with his socialist-inspired policies in Venezuela and abroad. He signaled as much in his victory speech, invoking figures from Jesus Christ to Pancho Villa as influences for his ambitious plans.

The tension between the campaigns of Mr. Chávez and Mr. Rosales reflected a polarized electorate in Venezuela, but by contrast the voting itself was largely tranquil, with few reports of clashes or other violence. Both candidates spent heavily in the race, with supporters for Mr. Chávez and Mr. Rosales each using American polling companies until well into Sunday evening.

Evans/McDonough, a polling company based in Oakland, Calif., and hired by Venezuela’s national oil company, released an exit poll indicating that Mr. Chávez was ahead, with 58 percent of the vote, to 40 percent for Mr. Rosales.

The results showed Mr. Rosales doing better than had been forecast in some polls, and his advisers said that quick counts indicated that he had won in several states and Caracas. But Mr. Rosales conceded defeat in a brief speech Sunday night, while saying the margin of Mr. Chávez’s victory was narrower than official results indicated.

“It’s been a hard fight against the mechanisms, all the dimensions of the government,” Mr. Rosales said.

Antonio Márquez, an official with Mr. Rosales’s campaign, said: “There’s been a great deal of pressure exerted by the government to demonstrate that they won. This climate of tension is not positive for the country.”

Other campaign officials for Mr. Rosales said soldiers had forced some polling places to remain open past the 4 p.m. closing time on Sunday to allow supporters of Mr. Chávez to vote. International observers in various parts of the country, however, said the election took place without signs of wrongdoing.

“One had to be moved by the earnestness and attention to detail,” said Martin Garbus, a trial lawyer from New York invited by Venezuela’s government to observe the election in Sarare, a town in the state of Lara. “It was a lesson in participatory democracy.”

Once the official results are in, how Mr. Chávez and Mr. Rosales react will determine whether Venezuela will return to the instability and street violence that had marred earlier elections. Mr. Rosales said Sunday night that he would continue leading the political opposition in the country, but it was clear that many critics of Mr. Chávez were hoping for a stronger response.

Still, the margin in Mr. Chávez’s favor reflected widespread support for the president as Venezuela reaps the economic benefits of high oil prices. Mr. Chavez has redirected government spending by creating an array of social welfare programs that benefit the poor.

In Caracas, voting at the Simón Bolívar elementary school in San Blas, a slum in the Petare district, proceeded calmly on Sunday morning. Once outside after voting, some voters put on red shirts and hats, indicating their support for Mr. Chávez. “I’m red, very red,” said Carlos Gelvis, an unemployed man from Petare, in a reference to a refrain of Mr. Chávez’s campaign.

Mr. Chávez voted in the 23 de Enero district, a stronghold of support for his “Bolívarian revolution,” which espouses distributing oil revenues to the poor. The president arrived to vote in a red Volkswagen Beetle and surprisingly extended what seemed to be an olive branch to the Bush administration.

He responded to remarks by Thomas A. Shannon Jr., the United States assistant secretary of state for the Western Hemisphere, in a Spanish newspaper, El País, which had quoted him as saying, “The political battle that is unfolding within Venezuela is now conducted through democratic institutions.”

Mr. Chávez said that Mr. Shannon “at least recognized we have democracy in Venezuela,” and added, “I think these are good signs.”

Amid all the voters clad in red clothing in 23 de Enero was Henry Borrero, who stood out with his faded blue polo shirt and his opposition to Mr. Chávez. “I want a free country where my 21-year-old son has the freedom to choose,” said Mr. Borrero, who accompanied his mother, who also said she had voted for Mr. Rosales. “Not one where you need a red shirt to get a job.”

Jens Erik Gould and Jose Orozco contributed reporting.