With Venezuelan President Hugo Chávez incommunicado and reportedly convalescing in Cuba, his brother told an audience that both arms and the ballot box could be used for Venezuela’s ruling party to retain power.

“As authentic revolutionaries, we cannot forget other forms of fighting,’’ Adán Chávez said at a prayer meeting in Barinas, Venezuela, that was devoted to the health of his 56-year-old brother, who grew up there.

Quoting Latin American revolutionary icon Ernesto “Che” Guevara, he added: “It would be inexcusable to limit ourselves to only the electoral and not see other forms of struggle, including the armed struggle.”

Adán Chávez , a mild-mannered former university physics professor who has a close relationship with the president while maintaining a low profile, did not explain why it might be necessary for the president’s backers to consider the possibility of guerrilla warfare in the future, and the statement seemed to clash with Hugo Chávez’s own assertions.

The comments came during a day of intense speculation that the leader may be gravely ill after reportedly undergoing emergency surgery 16 days ago.

Fernando Soto Rojas, president of the National Assembly, said rumors that Chávez has been diagnosed with cancer are false. He added that he expected the president to return home before July 5, Venezuela’s independence day.

Throughout South Florida, the news — or lack of it — prompted discussions of a post-Chávez Venezuela.

“If we can get rid of him, we’re not going to have another Fidel Castro in our country,’’ Pablo Cardenas said after a dinner with friends and family at Caballo Viejo, a popular Venezuelan restaurant in Westchester where photos of Venezuelan telenovela stars hang on the bulletin board.

Cardenas, a 55-year-old owner of a small scrap-metal business in Kendall, ate mondongo, Venezuelan tripe soup, and talked politics of his home country. At the table, a smiling Chávez looked out from the front page of El Venezolano, a Venezuelan paper published in Doral.

The photo, apparently taken in Havana, has the full-faced president in front of a hospital bed, one arm around Raúl Castro and the other bracing the hand of Fidel Castro, dressed in sweats and leaning on Chávez.

The image offered some context to the dinnertime speculation because South Florida has a checkered history with predicting the longevity of certain Latin American leaders. But even if illness did part Chávez from the presidency, what would it mean for Venezuela? There was no consensus Sunday night at the Cardenas table.

“That’s going to be a big problem for Venezuela,’’ said Miguel Fresneda, a longtime friend of Cardenas who was visiting from Valencia, where the Cardenases lived until 2000. He and his wife, Frances, talked of water and electricity outages at home, as well as a general fear the streets of Valencia weren’t safe under Chávez.

Fresneda predicted a power struggle should Chávez resign or die, which he said would likely be positive for his country. “That’s good for the opposition. I think it would be good for all of Venezuela.’’

At the adjoining table, José Maldonado wasn’t as confident in picturing a post-Chávez Venezuela. The New York-based sales executive for a mining equipment company was in Miami for a business meeting, then on to see clients throughout Latin America.

Maldonado, 51, said he was “no friend” of Chávez but wasn’t sure life would improve in his home country under a different president. “You cannot find a leader who’s going to lead the country to the next step,’’ he said. “It’s a big question mark. Who knows?’’

Despite assurances from top government officials and close relatives that Chávez is recuperating, the president’s silence and seclusion since the operation have spurred growing speculation about how ill Chávez might be.

Opponents say Chávez and his aides should be more straightforward.

“The uncertainty regarding Hugo Chávez’s health and considerable speculation over the real illness affecting him reveal the government’s serious constitutional violations,” said Miguel Angel Rodríguez, an opposition lawmaker.

Under Venezuela’s constitution, Chávez must “give us the diagnosis, talk to us about the treatment and answer questions,” Rodríguez said in a statement.

Venezuelan officials have said Chávez is recuperating, but have provided few details other than to say he is recuperating.

Chávez’s Twitter stream has been active, but it has not provided any information about his health. Three messages appeared within 30 minutes Saturday afternoon, including one mentioning visits by Chávez’s daughter Rosines and grandchildren.

“Ah, what happiness it is to receive this shower of love!” the Twitter message read. “God bless them!”

Nobody has heard Chávez speak publicly since he told Venezuelan state television by telephone on June 12 that he was quickly recovering from the surgery he had undergone two days earlier for a pelvic abscess. He said medical tests showed no sign of any “malignant” illness.

It remains unclear when he will return to Venezuela.

In Barinas, Chávez’s mother, Elena, wished her son a speedy recovery on Sunday.

“May the power of God heal him and bring him to me,” she told state television.

The vice president must take the president’s place during temporary absences of up to 90 days, according to the constitution. Some opposition politicians have suggested Vice President Elías Jaua should replace Chávez until he recovers, a move that Jaua has ruled out.

If Chávez were to relinquish power, some analysts believe his political movement would crumble or split.

“No one else is really ready to step in and take charge,” said Michael Shifter, president of the Inter-American Dialogue, a Washington-based think tank. “The current situation shows how precarious one-man rule is: Everything hinges on the whims of a single individual.”

“A search for a successor to Chávez would significantly scramble the country’s politics,” Shifter said. “A fierce power struggle within Chavismo would almost certainly ensue.”

Infighting also would likely break out within Venezuela’s loosely knit opposition, which plans to hold a primary to pick a presidential candidate for next year’s election.

“The opposition would also be thrown off balance,” Shifter said. “Their single-minded focus on Chávez has kept them more united in recent years.”

The president, a former paratroop commander, led an unsuccessful attempt to overthrow an earlier government in 1992. But he has repeatedly beaten his adversaries in elections since taking office in 1999 and he has long insisted that he is an authentic democrat who rules out violence as a means of holding onto power.

Despite numerous domestic problems ranging from soaring inflation to widespread crime, Chávez remains Venezuela’s most popular politician and he has vowed to win re-election next year.

Information from The Associated Press was used in this report, to which Miami Herald staff writer Douglas Hanks contributed.