But analysts have said it's difficult to determine who would succeed Chavez, whose personal charisma and popularity have led to throngs of followers who call themselves "Chavistas."
"You have to ask what's held things together in Venezuela. ... Part of what's held it together is that Chavez, despite his government's problems, is somebody who has a tremendous emotional connection and charisma with a lot of Venezuelans," said Michael Shifter, president of the Washington-based Inter-American Dialogue think tank.
"All of the people who are potential successors of Chavez are people who are polarizing and confrontational," Shifter told CNN earlier this year. "They're loyal to Chavez, but they don't have Chavez's ability to connect with most Venezuelans."
Polls have indicated 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 Maduro with 9.8% support among militant members of Chavez's United Socialist Party of Venezuela.
But that was before Chavez's remarks supporting Maduro on Saturday, which will likely bolster support for the vice president within the government and among fervent Chavistas, Corrales said.
"When popular presidents make an endorsement, that always has an effect," Corrales said. "This is an important thing that Chavez needed to do."
When he named Maduro as vice president in October, Chavez noted his extensive experience on "different battlefronts."
"The bourgeoisie make fun of Nicolas Maduro because he was a bus driver," Chavez said, "and look where he's going now."