"They couldn't defeat him electorally, they couldn't assassinate him, they couldn't beat him militarily," Jaua declared. "Chavez died as president ... Chavez died the leader of his people."
Just hours before the 58-year-old president's death on Tuesday, Maduro expelled two U.S. diplomats and lashed out at opponents at home and abroad. He implied that the cancer that ultimately killed Chavez was somehow injected into him by his enemies, a charge echoed by Ahmadinejad.
While Maduro is the clear favorite over likely opposition candidate Henrique Capriles, the nation is polarized between Chavez supporters and critics who hold him responsible for soaring inflation, a growing national debt and a jump in violent crime.
Opponents have also questioned the government's allegiance to the rule of law, arguing that Maduro is not entitled to become interim president under the 1999 constitution. They have also criticized the defense minister, Adm. Diego Molero, for pledging support for Maduro's candidacy despite a ban on the military taking political sides.
Ana Teresa Sifontes, a 71-year-old housewife and opposition sympathizer, said Chavez did some good for the nation's poor. But she said he had bungled the economy, exhibiting more interest in regional grandstanding than governing.
She said she hoped his death would bring change.
"Why do we have to pay for Cuba?" she asked, referring to the billions in Venezuelan oil Chavez sent to Havana each year in return for Cuban doctors and other experts. "Why do we need them here?"
Venezuelan officials have yet to say what type of cancer he suffered from, but details were emerging of the former paratrooper's final hours.
The head of Venezuela's presidential guard, Gen. Jose Ornella, told the AP late Wednesday that Chavez died of a massive heart attack after great suffering.
"He couldn't speak but he said it with his lips ... 'I don't want to die. Please don't let me die,' because he loved his country, he sacrificed himself for his country," said Ornella, who said he was with the socialist president at the moment of his death Tuesday.
In Washington, State Department Spokeswoman Victoria Nuland said the U.S. hoped the upcoming vote would be held on a level playing field, and lamented the expulsion of the American officials.
"We are obviously disappointed by these false accusations levied against our embassy officials," Nuland said. "This is part of a tired playbook of alleging foreign interference as a political football in internal Venezuelan politics."
Associated Press writers Fabiola Sanchez, Frank Bajak and Christopher Toothaker contributed to this report.
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