Venezuelans are choosing MPs, governors and other officials on Sunday.
The poll is being conducted against a backdrop of heightened government repression and opposition calls to boycott the election.
The election is the first to allow broad voter participation since last year's presidential contest, which President Nicolás Maduro claimed to have won despite credible evidence to the contrary.
It is taking place two days after the government detained dozens of people, including a prominent opposition leader, and linked them to an alleged plot to hinder the vote.
In the first hours after polls opened, members of the military outnumbered voters in some voting centres in the capital, Caracas.
No lines formed outside the centres, including the country's largest — a stark contrast with the hundreds of people gathered around the same time for the July 28 presidential election.
"I'm not going to vote," said truck driver Carlos León, 41, standing near a desolate polling station in Caracas.
"I don't believe in the (electoral authority). I don't think they'll respect the vote. Nobody forgets what happened in the presidential elections. It's sad, but it's true."
Voter participation, in the eyes of the opposition, legitimises Maduro's claim to power and his government's repressive apparatus, which after the July presidential election detained more than 2000 people including protesters, poll workers, political activists and minors, to quash dissent.
Meanwhile, the ruling party is already touting overwhelming victory across the country, just as it has done in previous regional elections regardless of opposition participation.
A nationwide poll conducted between April 29 and May 4 by the Venezuela-based research firm Delphos showed that only 15.9 per cent of voters expressed a high probability of voting on Sunday.
Of those, 74.2 per cent said they would vote for the candidates of the ruling United Socialist Party of Venezuela and its allies, while 13.8 per cent said they would vote for contenders associated with two opposition leaders who are not boycotting the elections.
"I think it's absolutely despicable," opposition operative Humberto Villalobos said on Saturday, referring to the election participation of some opposition members.
"We're facing the most brutal repression in recent years in the country. (The vote) is a comedy, a parody."
Voters trickled into polling places in an opposition stronghold in Caracas.
Some ignored the boycott calls based on the belief in their civic duty, while others saw the election as a chance to keep their local government under opposition control.
"I'm defending my municipality," said Edith, the owner of a bankrupt family business who declined to give her last name out of fear of government repression.
"I'm still angry with what happened in July, but I have to defend it."
Meanwhile, the US has denounced Maduro's government for setting up voting centres to elect representatives for Essequibo, a region disputed with Guyana.
Since the 19th century, Venezuela and Guyana have disputed this region of about 160,000 square kilometres, located west of the Essequibo River.
"The United States rejects all attempts by Nicolas Maduro and his illegitimate regime to undermine Guyana's territorial integrity, including this latest sham election in the Essequibo region," a US State Department account said on X.
with EFE