All this relies on either Chavez naming a successor to run in his place or, if he dies without doing so, with Cabello and Rangel Silva anointing someone to take his spot on the ballot. Cabello seems precluded from running himself because he is not well-liked by the Chavista base. And he's already lost once to the 39-year-old opposition candidate, Capriles.

"Cabello is not the most popular figure in the PSUV," Tinker Salas said

Polls indicate that although Chavez still has strong backing from his supporters, other possible successors don't seem to generate that kind of enthusiasm. A February poll by the Datanalisis firm showed Jaua with 15.7% support among militant PSUV members. Maduro had 9.8% support, el Aissami had 4.9% and Cabello had 2.8%.

Chavez's brother, Adan, had 8% support and is seen as another possible successor.

"The Cubans want to try to shoehorn Adan Chavez back into the scenario," Noriega said. "He's supposed to be a very hard-nosed guy."

That might be a tough sell for Cabello and Rangel Silva, though.

"When Adan was being groomed initially, it didn't sell with the military," said Noriega. "He wasn't one of them."

Adan Chavez also is seen as lacking his brother's drawing power.

"He has an open line to the president but doesn't have his charisma or his broad appeal," Tinker Salas said.

"But don't rule Adan out, because he is an ideologue and the Cubans are behind him," Noriega said. "Adan will be able to say, 'Vote for a Chavez.' And that's pretty damn significant. But he's not a warm and fuzzy figure. He's kind of clumsy. He's OK as a communicator."

Anyone named Chavez cannot be discounted, other analysts say.

"Adan Chavez has the Chavez name and the Chavez legacy," Tinker Salas said.

Carrasquero, the Venezuelan professor, also sees Adan Chavez as a viable candidate. And he also mentioned another possible candidate named Chavez -- the president's daughter, Maria Gabriela.

"She recently made a kind of announcement," Carrasquero said. "She basically said, 'Here I am. I have the same values as my father.' "

Noriega also touts Maduro's strengths as a possible candidate.

"Maduro is more liked," Noriega said. "He's an emotionally intelligent guy. My guess is they would go with Maduro. He's a bonafide working-class guy who would be able to reach out."

But he needs to convince Cabello and Rangel Silva that he can win, Noriega said.

And if Chavez is too ill to stand as the candidate, he will listen to his military backers, Carrasquero said.

"Maduro and Jaua are loyal to Chavez," he said, "but Chavez will give more weight to the military. He has a long relationship -- a sentimental relationship -- with the military."

Chavez also will listen to one other person, Carrasquero said.

"Chavez only pays attention to Fidel Castro," he said. "He does not allow anyone near him to tell him what to do or who has a different opinion."

Heavy-handed Cuban meddling might backfire, though, because there have been published reports of strong resentment among rank-and-file military against what many see as undue intrusiveness by the foreigners. Cabello and Rangel Silva would have to be mindful not to lose support from below. Chavez, after all, was but a mere lieutenant colonel when he staged his 1992 coup attempt.

The Cubans may only have the power to suggest and manipulate as best they can.

"I don't think they have the capacity to dictate," said Tinker Salas. "I don't think the PSUV would stand for that. I don't think the Venezuelan people would stand for that."

There's at least one more factor at play, and the Cubans are seen as having their hand in that too.