CARACAS (Reuters) - President Hugo Chavez has a solid 13-percentage point lead over opposition candidate Henrique Capriles in a new survey ahead of October's election - but many Venezuelans remain undecided.
The opinion poll by respected local firm Datanalisis found that 44 percent of voters favor Chavez compared to 31 percent for Democratic Unity coalition candidate Capriles, according to people who saw a private presentation.
No further details were available for the poll, which was to be formally published later in the week.
Chavez, 57, who is undergoing radiation therapy in Cuba after cancer surgery, remains popular into his 14th year in power due to his strong personal connection with the poor and heavy, oil-financed spending on welfare policies.
"The bourgeois are desperate," Chavez said in a speech from Cuba, promising a convincing win in the October 7 vote against a foe he derides as the epitome of Venezuela's wealthy elite.
"The only place they are going to govern is Pluto!"
Surveys consistently show, however, that up to a third of Venezuelans are undecided, indicating there will be a fierce battle between the Chavez and Capriles camps to win them over.
State governor Capriles, 39, is widely seen as the best hope the opposition has had of unseating Chavez after years of failures via the ballot box and street protests. He is embarking on a nationwide, "house-by-house" tour intended to give him national recognition and improve his poll standing.
The major wild card is Chavez's health.
He says his recovery is going quite well. Yet rumors persist among opposition journalists and diplomats citing medical sources, that his life is in jeopardy.
At the very least, it seems Chavez will be unable to run his usual all-energy, on-the-street campaign, whereas Capriles is projecting an image of youth and zest.
"The speed of Chavez' recovery from radiotherapy treatment will be key to determine how well he can manage his political campaign," said Diego Moya-Ocampos, a Venezuela analyst for IHS Global-Insight.
"Capriles has continued to capitalize on Venezuela's growing social and economic problems, together with issues of governance related to Chavez' refusal to delegate powers to his vice president during his treatment."
However, only one recent poll, by local firm Consultores 21, has put Capriles anywhere near Chavez, by placing him just 1 percentage point behind. Three surveys earlier in March found Chavez's support at between 52 percent and 57 percent, versus 22 percent and 34 percent for Capriles.
"The government has had since August last year a well-articulated strategy of public spending," said Asdrubal Oliveros, of local Ecoanalitica think tank, referring to the billions Chavez has poured into home-building, benefits for the poor and elderly, and other social projects.
"The opposition needs to get the details of its message across better if they are going to persuade a high percentage of the undecideds."
Capriles, a center-left politician campaigning on a platform of ending confrontation and solving grassroots problems, wants to bring Brazilian-style progress to Venezuela, with free-market economics alongside strong social welfare programs.
Chavez, known for his radical populism, nationalizations and fierce anti-U.S. rhetoric, has called him a "pig."
LINKUP FROM CUBA
Underlining the polarized nature of Venezuelan politics and the tense atmosphere this year, neither man refers to the other by name. Chavez calls Capriles "the candidate of the right" or "the loser candidate" while the governor calls the president "the candidate of the Socialist Party."
From Cuba, where he is receiving radiotherapy for five days prior to a planned return on the weekend, Chavez joined a live link with a ceremony in Venezuela for beneficiaries of state welfare projects. "The treatment's going well," he said, to cheers from supporters at home.
There had been speculation Chavez may seek an audience with Pope Benedict during his visit to the island, but he said he did not want to "interfere" with the pontiff's agenda.
The Venezuelan leader prefers treatment in Cuba because he is guaranteed discretion on the tightly controlled island and can lean on the counsel of his friend and mentor Fidel Castro.
In contrast with other high-profile figures around the region who have suffered cancer, Chavez has not allowed doctors or others give much official information on his own condition.
Beyond vague descriptions of the removal of two tumors in his pelvic area, details have been scant, leading to a frenzied rumor-mill and criticisms of excessive secrecy.
Chavez's health problems have played into markets and raised expectations of a change of government.
Venezuela's U.S. dollar-denominated debt, traded on international markets, has risen nearly 20 percent year to date, according to the JPMorgan EMBI Global index, second only to Ivory Coast's 27.6 percent rise in 2012.
So the recent clutch of opinion polls had been "disappointing for the 'regime change' camp", said Boris Segura, of Nomura Bank. He noted, however, that "six months is a long time in politics, and more particularly so when one of the contenders is not totally healthy."