Queues have generally been short and quick-moving at polling stations in the capital [AFP]
The city of Caracas awoke before dawn as fireworks and military bugles blaring from loudspeakers heralded the beginning of the referendum on term limits for elected officials, including Hugo Chavez, the president.
In previous referendums, residents say they had arrived during the night to join the long queues that formed at polling stations.
But this year, the queues were short and fast-moving in many areas of the city throughout the day - good news for voters but some opposition supporters seemed concerned that a low turnout could indicate a "yes" victory.
Rosario Espinal, a housewife from the mainly opposition-supporting district of La Trinidad, said she had voted against amending the two-term limit for presidents and some officials.
"I hope the 'no' vote wins but look at this," she said, pointing to the almost empty polling station behind her.
"There are no people."
Across the city groups of young Chavez supporters or "Chavezistas" wearing red t-shirts took to the streets on motorcycles to demonstrate support for the "yes" campaign.
Medina, a Caracas resident, believes Chavez will get his "yes" vote on Sunday.
Huge "si" ("yes" in Spanish) posters featuring Chavez or baseball stars dominate many of the major roads across the city, a symbol of the power of the government campaign.
After losing the last referendum in 2007, which included a similar proposal to remove term limits for the president, government activists have adopted an approach based on getting more of their supporters out to vote.
Local organisers across Caracas had signed supporters up to a "10 by one" system where each committed voter agrees to sign up 10 more for the Chavez campaign.
The campaign also organised transport for voters in some of the poorer parts of the capital, bringing the elderly and sick to the polling stations to vote.
And the government had also made subway transport free for the day in an attempt to increase turnout.
Maudilio Medina, a Chavez-supporting activist in the Mexico Avenue area of Caracas, said there were a lot of "yes" campaign supporters attending polling stations there.
"We won't lose," he said. "Everything is going very well."
In the poor slums or "barrios" of Caracas where many of the city's residents live, Chavez supporters were out in force.
|Medina, a Caracas resident, believes Chavez will get his "yes" vote on Sunday
"I am with the government until death," said Argenis Aray, a salesman in the Las Minas barrio in the southeast of the city.
Aray voiced concerns that appeared to motivate many of Chavez supporters - that the hugely popular social programmes to help poor Venezuelans would be under threat following an opposition victory.
He said that such programmes, which include the nationalisation of the local school, were already in jeopardy after the opposition ousted the Chavez party from power in the area during recent local elections.
Following a low-key campaign, the opposition, which denies it will make any cuts to the programmes, appeared to have adopted a strategy based on monitoring the vote in order to report any alleged irregularities.
Students, who formed the heart of the "no" campaign set up a special telephone call centre in Caracas to collate reports from monitors across the country.
Alexis Escobar, a student activist at the Central University of Venezuela, said he remained confident about the opposition's chances and that reports they received said there was a high turnout of voters in most of big cities.
|"No" vote campaigners have made low-key attempts to convince supporters [AFP]
"No" campaigners also took to the streets in opposition areas, with yellow painted trucks touring the city as supporters made a last ditch attempt to convince residents to vote.
And even in the Chavez-supporting districts such as Centro, "no" voters were still prepared to speak out.
Luis Olodarno, a mathematics teacher, said he had voted no because there were others who were capable of governing the country and they should be given a chance.
"Chavez has dedicated too much of his time to solving the problems in other nations," Olodarno said of Chavez's high profile on the international stage.
"He has ignored problems at home."
It remains to be seen whether enough Venezuelans agree with him to deny Chavez his goal of abolishing term limits to further his "Bolivarian revolution".