
In the western state of Zulia, where the opposition won 12 of the 15 posts up for grabs, Gov. Pablo Perez attributed the opposition's gains to the coalition's decision to field a single candidate for each of the 165 seats being contested.
"We showed Venezuela that we can advance if we're united," Perez said.
Miguel Tinker Salas, a professor at Pomona College in Claremont, California, said the outcome could prompt Chavez to concentrate on resolving pressing domestic problems, which include rampant violent crime, a lingering economic recession and Latin America's highest rate of inflation.
"It might force him to be more pragmatic and increasingly more focused on internal matters, especially now that he's got his eye looking toward 2012," when he faces re-election, Tinker Salas said.
Still, the opposition lacks a strong presence in many of the rural states where Chavez remains most popular, making it more difficult for government foes to win strong backing for a presidential candidate within two years, Tinker Salas said.
Polls suggest Chavez remains the most popular politician in Venezuela, yet surveys also have shown a decline in his popularity in the past two years as disenchantment has grown over the nation's persisting domestic problems.
The opposition, which boycotted the last legislative elections in 2005, dramatically increased its representation beyond the dozen or so lawmakers who defected from Chavez's camp in the current National Assembly.
The opposition's goal was to win a majority of the assembly's seats. Even though they fell short, they will be able to put some constraints on Chavez's lawmaking power because they prevented his allies from winning a two-thirds majority.
"There's going to be some paralysis in the assembly because many decisions require a two-thirds majority, it's going to put some brakes on Chavez's project," said Gregory Wilpert, author of the book "Changing Venezuela By Taking Power."