Uncertainty rules these days in Caracas and across Venezuela, after President Hugo Chávez's cancer relapse and his sudden announcement that he will undergo a fourth cancer-related surgery.

Underlining the gravity of the situation, Vice President Nicolás Maduro broke into tears on Monday at a political rally hours after Chávez flew to Havana.

"Chávez has a nation, he has all of us, and he'll have all of us forever in this battle," said Maduro, who wiped away tears while speaking to supporters. "Even beyond this life, we're going to be loyal to Hugo Chávez."

Even beyond this life, we're going to be loyal to Hugo Chávez

- Nicolás Maduro, Vice President of Venezuela

Maduro called for the president's supporters to rally behind his candidates in upcoming gubernatorial elections on Sunday, and he also inaugurated a new cable car system in a poor neighborhood. Maduro, who spoke passionately and wore the red of Chávez's socialist movement, seems set to take on a larger role as the president's chosen successor.

Chávez said for the first time on Saturday that if he suffers complications, Maduro should take over for him and should be elected president to continue his socialist movement.

Analysts say Maduro faces monumental challenges in trying to stand in for his mentor and hold together the president's diverse "Chavismo" movement, while also coping with economic problems that are weighing on the government.

Maduro may inherit political power, "but he definitely can't inherit the charisma" of Chávez, said Luis Vicente Leon, a pollster who heads the Venezuelan firm Datanalisis. He said that during his nearly 14 years in office Chávez has been the glue that has held together groups from radical leftists to moderates, as well as military factions.

Leon said it's unclear if Maduro has what it takes to hold the movement together if Chávez dies. "Internal divisions could make the revolution unstable in the future," Leon said.

Political analyst Vladimir Villegas, who has known Maduro since his adolescence, said the vice president's experience years ago as a public transit union leader will probably help him in the difficult task of mediating between different groups of Chávez allies.

In a radio interview Tuesday morning, former presidential candidate Henrique Capriles ruled out the idea that he is already planning a presidential run. 

"I'm not doing the math nor desire that to be the scenario," he said, referring to Chávez’s eventual passing.

He said he hopes that Chávez is able to assume power on January 10. 

"The President promised villas and castles during the election, he got more votes than what we got on October 7, so the government must keep its promise to the Venezuelan people," he said during an interview with Exitos radio station. “What will happen only the President and God knows."

About the government model created by the President, Capriles said "There is no chavismo without Chávez", adding that the country's problems have been offset by the President’s charisma and his followers’ loyalty.

"But if you take away the face of the President (from the ruling party), what do you have?" he pondered.

Before leaving for Havana early Monday, Chávez met with military commanders at the presidential palace and promoted his defense minister, Diego Molero, to the rank of admiral in chief. Chávez showed Molero and other military commanders a golden sword that once belonged to independence hero Simon Bolivar.

Holding the sword, Chávez told the officers that he fully trusts them. He also warned of potential conspiracies by enemies, both foreign and domestic.

"I'm totally sure that our homeland is safe," Chávez told them. He urged them "not to give in to intrigue."

With reporting by The Associated Press.

Follow us on twitter.com/foxnewslatino
Like us at facebook.com/foxnewslatino