The entire military high command is appointed by Chavez. San Miguel estimates there are 300 hardcore Chavez loyalists in the officer corps, while mid- and lower-level officers aren't necessarily politically allied.
If there is no clear-cut winner in Sunday's vote, or if the opposition wins by a narrow, contested margin, San Miguel believes the greatest threat of violence would not come from the military, but from pro-Chavez militias: "armed bodies that operate outside the law and that in the past have appeared after polls close."
Many Venezuelans believe members of the militias, estimated to number more than 100,000, are little more than thugs.
Their leaders don't report to the armed forces, but rather directly to a military officer under Chavez, San Miguel said.
One local militia leader, Raiza Urbina, talked with the AP on Friday in the community center that she calls "The Fortress" in the Caracas slum of Petare and said she would not accept a Capriles victory.
"We have a Plan B," Urbina said when asked what she would do in that case with the 398 well-armed militiamen she says she commands.
She refused to disclose it.
"You can interview us when we implement it," added the feisty Urbina, her pate bald from chemotherapy for breast cancer that she said had spread to her liver.
AP reporters saw a half dozen militiamen at the center, some toting shiny new Kalashnikov assault rifles.
The center, a shrine to communist leaders from Ho Chi Minh to Fidel Castro, also is a polling place. Six voting machines in sealed suitcases were stored inside. Urbina said militiamen would provide Election Day security there.
There has been sporadic pre-election violence.
Pro-Chavez activists have tried to block opposition rallies and marches, and two Capriles supporters were shot to death during a campaign caravan last Saturday in Barinas, the president's home state.
The opposition also fears soldiers could be pressured to vote for Chavez. Soldiers got the right to vote in 1999 during Chavez's first year in office. Soldiers vote in the polling centers where they're registered, along with civilians.
Electoral officials and political leaders on both sides have assured the public that safeguards are in place to ensure the vote is secret, but some Venezuelans still fear that thumbprint readers used to verify identities at polling stations might enable the tracking of voters' choices.
Chavez, who was first elected president in 1998, has surrounded himself with soldiers, active and retired. Five of Chavez's roughly 30 Cabinet ministers are either current or former military officers, including those in charge of health, food and public banks.
They also occupy such vital posts as president of the National Assembly and have been elected governors of some of Venezuela's biggest states.
Some top officials have stronger motives to hope Chavez remains.
The current defense minister, Rangel, is among seven members of Chavez's inner circle whom the United States put on its foreign drug kingpins list, accusing them of supplying Colombia's main leftist rebel group with arms and aiding cocaine-trafficking operations.
Washington has frozen any assets they might have in the United States and barred Americans from doing business with them.
The U.S. government says Venezuela continues to be the main point of departure for northbound drug flights from South America.
Associated Press writers Vivian Sequera and Fabiola Sanchez contributed to this report.
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