Romulo Betancourt, the Venezuelan embodiment of the ideals that inspired the Alliance for Progress two decades ago, died yesterday in New York City following a stroke. As the first elected Venezuelan president to complete his term, 1959-64, he started a democratic tradition in that country that continues today.

Mr. Betancourt, 73, had moved to New York last month from Caracas with his second wife, a physician, for the announced purpose of completing his memoirs. A spokeswoman for Doctors Hospital, quoted by Associated Press, said he died of complications from a stroke and fall at his Manhatten apartment Thursday.

The feisty founder of the moderately leftist Democratic Action party lived much his life abroad, in enforced exile during the early years and by choice since the late 1960s. He stayed variously in Costa Rica, Puerto Rico, Chile, Cuba, Switzerland and Washington, living with his first wife in a Northwest bungalo for six months ending June 1950.

President John F. Kennedy repeatedly pointed to Betancourt as a model for leadership of the new Latin America expected to emerge from the massive infusion of aid and expertise known as the Alliance for Progress.

In a state dinner for Betancourt in February 1963, Kennedy sought to make a clean break with a past U.S. record of close dealings with dictators. "We wish the United States to be identified with leaders such as you," said Kennedy.

At that time, Mr. Betancourt still seemed unlikely to complete his own presidential term. He had been the target of a bomb attack three years earlier that seriously injured him, scarring his face and arms, and killed an attache at his side. The attack was attributed to henchmen of the then dictator in the Dominican Republic, Rafael Trujillo.

Mr. Betancourt survived at least one other attempt on his life and numerous overthrow plots involving Venezuelan military dissidents. Having seen his earlier efforts at democratic rule fail that way, he by then made a point of including the officer corps in his constituency. "He rarely missed a military school graduation or a chance to hand out a ceremonial sword," said a U.S. diplomat at the time.

The hopeful democratic prospects for Latin America that presidents Kennedy and Betancourt dwelled upon did not last long after the American's death.

When South America's traditional democracies in Chile and Uruguay fell to coups in 1973, the Venezuelan tradition that had started so shakily with Mr. Betancourt in 1959 became the longest-running constitutional rule on the continent.

In 1968, when his Democratic Party lost power -- by the ballot box -- to its Christian Democratic rivals, Mr. Betancourt invited reporters to his modest house on the outskirts of Caracas. It was a crucial stage in the oil-rich but tumultuous nation's political development. Many Venezuelans were unsure the party could bring itself to hand over power.

"The democratic game is a little like baseball," he said. "The pitches keep on coming." He allowed as how his party had just missed one with the electorate that year and would be back in the game later. It won the next elections five years later.

Mr. Betancourt served the reporters watermelon punch that day. His unpretentious house and austere style were important symbols in a society given to splashing about in the new wealth that oil afforded it.

Born in a small town near Caracas, Mr. Betancourt showed scholastic talent that carried him to the university and student politics. He was jailed, then exiled for demonstrating against the dictator of the time and while in Costa Rica, at age 22, he briefly was a member of the Communist Party.

Back in Venezuela, he gradually became strongly anticommunist. He had several ways of dismissing the meander from his social democratic path, the favorite being that it was "a youthful attack of smallpox that left me immune to the disease." That immunity was not recognized by the John Birch Society in the United States, which attacked him repeatedly in the 1960s as a communist.

At about the same time, he led the successful effort to have Cuba expelled from the Organization of American States for having smuggled arms into Venezuela for left-wing guerrillas.

Mr. Betancourt actually served twice as president -- the first time provisionally, at the head of a junta, in 1945. He had joined forces with military dissidents to oust a dictator. He arranged for elections as promised in 1947 and backed the successful campaign of the nation's premier poet, and Mr. Betancourt's old professor, Romulo Gallegos.

When Gallegos tried to move fast on all fronts toward social democratic goals, he soon was ousted by yet another dictator, Marcos Perez Jimenez, and Mr. Betancourt went into 10 years of exile.

With the ouster of Perez Jimenez in 1958, Mr. Betancourt returned and easily won the subsequent elections. His rule saw major reforms, undertaken at a more measured pace than in the past, but his major accomplishment was to have endured in office.

Encouraged by his aggressive minister of mines, Juan Pablo Perez Alfonso, Mr. Betancourt negotiated a then-extraordinary 50-50 profits split with the major oil companies producing in Venezuela. Perez Alfonso was a founder of OPEC and is considered its main inspiration. As austere in his life as Mr. Betancourt, he died two years ago.

Mr. Betancourt had a wealth of ego. The Venezuelan government, at his insistence, published an eight-volume set of his papers that was distributed, massively, in Spanish worldwide.

His close association with president Kennedy put him in a difficult position with successor Lyndon Baines Johnson. Mr. Betancourt joined the hemisphere-wide outrage when Johnson sent U.S. Marines to the Dominican Republic in 1965.

But when Johnson called on him to help patch up the split with Latin America over the intervention, he stoically carried out the task.