"They have a whole soap opera," Chavez said, referring to the opposition. "We're going to show them what revolutionary unity is!"
The 57-year-old leader has been in office since 1999 leading his socialist-oriented Bolivarian Revolution movement, named after 19th century independence hero Simon Bolivar. Chavez is seeking another six-year term in the October presidential vote.
His rival, 39-year-old state governor Henrique Capriles, has criticized Chavez's secretive handling of his cancer, saying that if he were president, his health would "be a matter of public knowledge."
"We welcome home the government's candidate," Capriles said while making door-to-door pre-campaign visits in Aragua state. "I wish him good health. He shouldn't forget that in this contest ahead, at least from our part, what we're doing is going house-to-house. It's not insulting anybody."
Chavez called the opposition "the bourgeoisie" and the "stateless and irrational right." He referred to Capriles as the candidate of "the Yankees."
"The beating we're going to give the Venezuelan right, the beating we're going to give them, that beating is going to be memorable," Chavez said.
Associated Press writer Jorge Rueda contributed to this report.
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