President Hugo Chavez needs to rely on a vast get-out-the-vote machine to avoid an unprecedented defeat when Venezuelans cast ballots on Sunday in a referendum on letting him run for re-election indefinitely. Used to winning votes easily, the self-styled revolutionary trailed by a few points in most surveys over the past few days.
But pollsters say the narrow gap puts him in a statistical tie with the "No" camp and that his disciplined, state-backed political machinery could give him an advantage on vote day. One survey on Wednesday by Consultores 30.11, which has worked for the government and accurately predicted a result last year, showed Chavez moving ahead - by at least 7 points.
Buoyed by the Opec nation's record oil prices, the leftist is a leading US critic. Quick to hurl insults at foreign leaders, the Cuba and Iran ally also enters the vote in a diplomatic dispute with Colombia, Spain and the United States.
In office since 1999, Chavez wants a constitutional overhaul that includes permitting him to run again in 2012 and then to stay in power as long as he keeps winning elections.
Chavez is popular among the majority poor for funnelling oil income into schools, clinics, and food subsidies. Still, he faces the stiffest resistance to date among his own backers to his vision of a socialist state inspired by his mentor, Cuba's Fidel Castro.
Washington brands the leader of a failed 1992 coup as a destabilising, anti-democratic force in Latin America, where his allies in Bolivia and Ecuador are also pushing left-wing reforms with constitutional rewrites. He burnished his nationalist credentials on Wednesday by cutting diplomatic ties with Colombia after the collapse of mediation talks with rebels in the Andean neighbour.
His foreign minister also said Venezuela could expel a US diplomat on suspicion of working against the reform. Chavez, 53, says he needs a new mandate to extend his programs for the poor. "The reform is essential ... to avoid the revolution losing its way, or pausing or worse still sinking," Chavez said.
He said he would prepare his suitcases, ready to leave office in 2013 should the reform fail. If he wins, he promises 150 new laws. Chavez used a mandate from a landslide re-election a year ago to nationalise swaths of the economy, shut the last nationwide opposition TV channel and rule by decree.