As Maduro temporarily assumes the presidency, analysts have said it's difficult to tell whether anyone else from Chavez's United Socialist Party of Venezuela will have what it takes to win at the polls.
They note that Chavez's political strength was largely fueled by his ability to personally connect with throngs of dedicated followers -- dubbed "Chavistas" for their devotion to the president.
And that personal connection with his supporters is "what's held things together in Venezuela," according to Michael Shifter, president of the Washington-based Inter-American Dialogue think tank.
Polls have indicated that several possible successors from within the party's ranks haven't generated the same kind of enthusiasm among Chavez's supporters. A February 2012 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, which were seen as likely to 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.
When he named Maduro as vice president, 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."