By Andrew Cawthorne
CARACAS (Reuters) - Rallying supporters with folk tunes and jokes, President Hugo Chavez bade an emotional farewell while supporters prayed for him around Venezuela ahead of Friday's planned departure for cancer surgery in Cuba.
The announcement he needs another operation for a likely malignant lesion gave the lie to Chavez's previous claims of full recovery and threw the South American OPEC member's October 7 presidential election into uncertainty.
Chavez says he may need radiotherapy treatment after the operation scheduled for early next week in Havana - where he first had surgery for a cancerous pelvic tumor last year - raising the prospect of another lengthy convalescence.
Yet he has been upbeat in a stream of public appearances about quickly "conquering" his latest health setback.
"I dreamt a while ago of Christ who came and said 'Chavez, rise, it is not time to die, it is time to live'," he said, in one story recalling the Biblical story of Jesus raising Lazarus from the dead.
"If the cancer is back, I declare it 'squalid' and it will be dealt with mercilessly and defeated," he said, using a term he coined years ago to pillory Venezuela's opposition.
Telling anecdotes from his infancy and singing Venezuelan folk songs to the accompaniment of traditional instruments, Chavez sought to raise supporters' spirits in a lengthy evening ceremony at a Caracas theater carried live, by government order, on all Venezuelan TV channels.
Around the nation, supporters concerned about Chavez's health organized religious services and sent him messages. One group sculpted a heart shape in coastal sand dunes that are a popular tourist spot in western Venezuela.
State TV dusted off old images of a young Chavez rallying crowds, kissing children and playing sports.
"We are the majority; there's no room for sadness," the socialist leader told supporters who cheered and applauded his every word at the Thursday evening ceremony.
"This was never in the plan for 2012 but those are God's ways and I am ready to face any difficulty."
Chavez's health woes have sent Venezuelan bonds higher on investor hopes for a more market-friendly government.
Opposition leader Henrique Capriles, the 39-year-old governor of Miranda state who takes the center-left Brazilian government model as his inspiration, is to face him in an October 7 vote.
While Chavez, 57, may benefit from a wave of sympathy, perceptions of physical weakness - particularly in contrast with Capriles' image of youth and energy - could offset that.
Prior to the announcement of his new surgery, opinion polls had shown Venezuelans broadly divided, with a third pro-Chavez, a third pro-opposition, and a third undecided.
However, the polls also gave Chavez a small edge in voter intentions - a fact analysts attribute to his popularity among Venezuela's poor and an increase in spending on welfare for the most needy.
In opposition circles, there is speculation the election might be delayed until later in the year to give Chavez time to recover from his latest surgery and mount an energetic campaign.
Though ruling Socialist Party members are under instructions not to discuss succession questions publicly, media and political circles are rife with gossip over who, if anyone, might replace Chavez should he be incapacitated.
Dominating Venezuela since his first 1998 election win, Chavez has avoided grooming a successor.
None of the main figures around him have his charisma, political and rhetorical skills, or connection with the masses.
In a paper titled "The beginning of the end," Venezuela analyst Alejandro Grisanti of Barclays Capital in New York said Capriles would be the winner if Chavez's health problems are prolonged.
"If Chavez is out of the race, the chance for the opposition to win the election increases considerably," he said of the Democratic Unity coalition, which has united Venezuela's diverse opposition groups after years of in-fighting.
"Given the strong victory of Henrique Capriles in the primary, we consider a division in the opposition side to be unlikely. Meanwhile, the chances of division in the government are greater."
Chavez was due to fly to Cuba on Friday afternoon.
He has chosen Havana over an offer from Brazil and some calls for him to show support for Venezuela's health system, because he is guaranteed discreet treatment by friendly authorities and reduced chances of media leaks there.
He will also be able to enjoy the company of his mentor and friend Fidel Castro, the former president of Cuba.
(Additional reporting by Mario Naranjo, Deisy Buitrago and Girish Gupta; Editing by Eric Walsh)