CARACAS — Venezuelans awakened on Monday to the prospect of another six years under President Hugo Chavez, as the leftist president’s supporters celebrated his victory against a youthful rival and a galvanized opposition pledged to build on its gains.
Chavez emerged from Sunday’s vote both strengthened and sobered, having reconfirmed his masterly political touch but also winning by his tightest margin yet. Challenger Henrique Capriles, conceding defeat, said that his campaign had launched a new political force and that he would keep working for change.
The 58-year-old president now has a freer hand to push for an even bigger state role in the economy and deepen friendships with US rivals. Meanwhile, he is under pressure to address nuts-and-bolts governance issues such as soaring crime rates, power blackouts, and double-digit inflation.
With a turnout of 81 percent, Chavez only got 551,902 more votes this time around than he did six years ago, while the opposition boosted its tally by about 2.1 million. Chavez appeared to acknowledge the opposition’s growing clout during a boisterous victory speech late Sunday night.
‘‘I extend from here my recognition of all who voted against us, recognition of their democratic weight,’’ he told thousands of cheering supporters from a balcony of the presidential palace after midnight.
Capriles, a former state governor, had accused the flamboyant incumbent of unfairly using Venezuela’s oil wealth to finance his campaign as well as flaunting his near-total control of state institutions.
Still, he accepted defeat as Chavez swept to a 10-point victory margin. The former army paratroop commander won nearly 55 percent of the vote against 45 percent for Capriles, with more than 95 percent of the vote counted.
‘‘It was the perfect battle!’’ Chavez told his supporters. The crowd responded with chants of ‘‘Chavez won’t go!’’
Chavez spent heavily in the months before the vote, building public housing and bankrolling expanded social programs. With the largest proven oil reserves in the world, Venezuela has received hundreds of billions of petrodollars over the past decade.
‘‘I think he just cranked up the patronage machine and unleashed a spending orgy,’’ said Michael Shifter, president of the Washington-based Inter-American Dialogue think tank.
But Shifter also noted the affinity and gratefulness Venezuela’s poor feel for Chavez. ‘‘Despite his illness, I still think he retains a strong emotional connection with a lot of Venezuelans that I think were not prepared to vote against him.’’
Perhaps the top question facing Chavez is whether he has truly beaten cancer, after having two rounds of surgery since June 2011 to remove tumors from his pelvic region as well as chemotherapy and radiation treatment. He has said his most recent tests showed no sign of illness.
Venezuela would have to hold a new election if Chavez were forced to step down during the first years of his term.
Without referring to his cancer, Chavez said in his victory speech: ‘‘I ask God to give me life and health to keep serving the Venezuelan people, more and better every day!’’
Both sides now turn to regional elections scheduled for December, in which Venezuelans will choose state and municipal leaders.
While fireworks exploded over downtown Caracas, Chavez supporters said Sunday night they were prepared to turn back local victories scored by the opposition in recent years.
‘‘It’s time now to sweep away the squalid ones,’’ said Ignacio Gonzalez, using a description of the opposition Chavez employed during campaigning. The 25-year-old student wore a red shirt that wedded the images of Chavez, Jesus Christ, and South American independence hero Simon Bolivar.
‘‘It’s time to get them out of governor’s and mayor’s offices,’’ he said. ‘‘The next battle is in December.’’
Opponents pointed out that they had posed the strongest challenge yet to Chavez, who won by a 27-point margin in 2006 and by 16 points when he was first elected in 1998.
‘‘I will continue working to build one country,’’ said Capriles, the 40-year-old grandson of Holocaust survivors, in his concession speech. He said he rejected the idea of two Venezuelas divided by ideology and class and asked Chavez to rule for all Venezuelans.
A Capriles victory would have brought a radical foreign policy shift, including a halt to preferential oil deals with allies such as Cuba, along with a loosening of state economic controls and an increase in private investment.