For Jorge Batlle, the 72-year-old scion of a political dynasty in Uruguay who took his fifth shot at the presidency today, persistence finally paid off.

Batlle, candidate of the ruling centrist Colorado Party who promised a cautious approach toward the economic reforms that have swept over much of Latin America in the 1990s, was leading his more left-wing rival, Tabare Vazquez, 59. With 100 percent of the votes counted, Batlle had 52 percent of the vote in the runoff election, compared with 44 percent for Vazquez, and Vazquez conceded defeat at 9:40 p.m. Final official results were expected Monday.

The campaign focused on fears that Uruguay might follow the lead of its giant neighbors, Argentina and Brazil, and embrace rapid free-market reforms that could lead to the selling off of state-run enterprises and tinkering with the century-old welfare state. Almost 1 in 5 Uruguayans works for the government, and generous social programs and high taxes on industry have given the nation the lowest poverty rate in Latin America.

The anti-reform sentiment in Uruguay highlights a growing sense of caution about free-market programs throughout Latin America, as high unemployment, increasing poverty and recessions have hit many countries that embraced the programs. In Uruguay, which has undertaken only minor reforms to date, the economy has been dragged down by recessions in neighboring Argentina and Brazil, and unemployment has risen to 11 percent.

Batlle, whose great-uncle, a former president, was the architect of the welfare state here almost a century ago, swore that he wouldn't be the architect of its destruction. Once in favor of privatizing state industries, he quickly changed his mind after voters overwhelmingly rejected the idea in the early 1990s. Since then, he has repositioned himself as the candidate who could boost trade and foreign investment while retaining Uruguay's progressive social programs.

"This nation from its origin to today," Batlle said in his victory speech, "has not survived off its size or its strength, but off its [sense] of society. This has always been our strength, and that . . . will continue to help us build a great nation."

Vazquez, whose Broad Front coalition includes Socialists, Communists and ex-Tupamaro guerrillas, won the first round of the election last month, garnering 39 percent to Batlle's 32 percent. But Batlle made up substantial ground on two fronts: He won the endorsement of the center-right National Party, and he succeeded--partly through missteps by Vazquez and his advisers-- in portraying the Broad Front as too leftist to govern.

Toward the end of the campaign, Vazquez spent more time managing inflammatory statements by Communists in his coalition--who still wear T-shirts bearing the name of Fidel Castro's legendary lieutenant, Ernesto "Che" Guevara--than squaring off against Batlle.

And, in a nation with some of the highest tax rates in Latin America, Batlle hammered Vazquez's proposal to levy a new income tax.

Julia Bonino, 39, a nurse voting outside a school in a middle class neighborhood of Montevideo, said, "I consider myself left-wing, but I voted for Batlle."

"I think there are too many extremists with Vazquez," she said. "It makes me uncomfortable. Batlle, I think, will keep [economic] changes moving ahead, but very slowly and without forgetting that government must be the policemen of private companies and foreign investors."

Although Batlle won, analysts called the unprecedented support for the Broad Front a victory for the left. The difference between the two candidates' support was estimated at only 160,000 votes.

Indeed, support has more than doubled for the Broad Front since the mid-1980s, when it was considered a relatively minor political force.

Gains made in legislative elections in October gave the front a plurality in both houses of Congress for the first time.