CARACAS, Venezuela (CNN) -- One day after demonstrators thronged the Venezuelan capital's main thoroughfare to express their opposition to Sunday's referendum on changes to the constitution, supporters of President Hugo Chavez plan to hold their own demonstrations on Friday.
A banner in Caracas supports the constitutional reforms sought by Venezuelan president Hugo Chavez.
Tens of thousands of people filled Avenida Bolivar from early in the morning Thursday to voice fears that approval of the 69 proposed amendments would give Chavez a tighter grip on power and lead to a totalitarian state.
Both sides have declared they will emerge victorious. Recent polls have put the odds at about even.
At stake is whether the leftist leader should have full authority over the now autonomous Central Bank and the nation's economic policy. Chavez has said the changes are necessary to move the economy toward socialism.
The most controversial amendment would do away with term limits, allowing the 53-year-old firebrand president, who has already served almost eight years in power, to hold the office indefinitely as long as he is re-elected. Watch what else is being proposed »
The constitution is the one Chavez helped write when he was voted into office in 1998, promising to rid the country of corruption. He was twice re-elected by large margins and is not due to leave office until 2013.
The peaceful demonstration on Thursday contrasted with others in recent days, when riot police fired tear gas and water cannon jets at university students, as they tried to take their protests off university grounds.
Early this month several anti-Chavez demonstrators were wounded by gunfire. And on Monday, a student was killed during a rally in the state of Maracaibo. The shootings are under investigation, a government spokesman said.
Chavez insists the majority of Venezuela's 26 million people back him, and indeed he has garnered overwhelming support from the country's poorer neighborhoods, who have benefited from his policies -- paid for by skyrocketing oil prices. Oil accounts for roughly 90 percent of the country's export earnings, according to the CIA World Factbook.
Among the benefits reaped by Venezuela's impoverished classes have been free health care and education -- the same benefits accorded Cuba's poor under Chavez's friend and mentor, Cuban President Fidel Castro.
But Raul Baduel, a former Venezuelan defense minister who has broken with Chavez, earlier this month called Sunday's vote a coup. "They're attempting to usurp the constitutional powers of the Venezuelan people," he told CNN.
Venezuelan Deputy Chief of Mission Angelo Rivero ridiculed Baduel's remarks, saying, "If General Baduel believes this is a coup d'etat, it would be the first time in history that a coup d'etat is voted for by the majority of the people."
Chavez, a former paratrooper, routinely thumbs his nose at the United States and has called his U.S. counterpart, George W. Bush, "the devil."
On Wednesday, he accused the United States of pushing Colombian President Alvaro Uribe to end Chavez's efforts to broker the release of hundreds of people kidnapped by Colombian leftist rebels.
Chavez does have warm relations with Iran's President Mahmoud Ahmadinejad and has joined in his call for the oil-producing cartel OPEC to switch to euros from dollars, which Ahmadinejad has called "worthless." Their recommendation was rejected.
Despite the animosity, the United States and Venezuela remain closely tied economically: The United States is Venezuela's biggest oil customer and one of the few countries that can refine its low-quality crude.
Chavez survived a botched, two-day coup attempt in 2002 and has accused the United States of having supported anti-democratic forces. E-mail to a friend
CNN's Harris Whitbeck and Flor Santamaria contributed to this story.
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