(Adds U.S. comments, international protests)

By Vivian Sequera and Corina Pons

CARACAS/BARQUISIMETO, Venezuela, May 20 (Reuters) - V enezuela's leftist leader Nicolas Maduro looked set to win re-election on Sunday in a seemingly poorly attended vote condemned by foes as the "coronation" of a dictator and likely to bring fresh foreign sanctions.

Despite his unpopularity over the OPEC member's economic meltdown, the 55-year-old former bus driver was benefiting from a boycott by the mainstream opposition, a ban on his two most popular rivals, and state institutions in loyalists' hands.

The vote could trigger new sanctions from the United States, and more censure from the European Union and Latin America.

U.S. Deputy Secretary of State John Sullivan said on Sunday the Trump administration would not recognize the election and was considering oil sanctions. U.S. Secretary of State Mike Pompeo called the election a "sham."

Maduro, the self-described "son" of former leader Hugo Chavez, says he is battling an "imperialist" plot to crush socialism and take over Venezuela's oil reserves. But foes say he has destroyed a once-wealthy economy and ruthlessly crushed dissent.

Maduro's main challenger is former state governor Henri Falcon, who predicted an upset due to fury among Venezuela's 30 million people at their increased poverty.

Though some polls showed Falcon ahead, analysts say his chances are thin given widespread abstention, the vote-winning power of state handouts, and Maduro's allies on the election board.

Results were expected by late evening.

In voting stations visited by Reuters reporters, from wealthy east Caracas to the Andean mountains near Colombia, attendance appeared far lower than the last presidential election in 2013 when there was an 80 percent turnout.

There were lines, however, outside polling stations in poorer government strongholds, where the majority of voters interviewed said they were backing Maduro.

"I'm hungry and don't have a job, but I'm sticking to Maduro," said Carlos Rincones, 49, in the once thriving industrial city of Valencia, accusing right-wing business owners of purposefully hiding food and hiking prices.

The government has set up so-called "red point" zones near polling stations so Venezuelans can scan their state-issued 'fatherland card' used to receive benefits including food boxes and money transfers. Maduro has promised a "prize" to those who do so. Critics say this is a way of scaring impoverished Venezuelans into supporting his government.

Falcon said his team had received some 350 complaints about the "red points." Three state workers also told Reuters they were pressured to vote, while pro-government activists hovered around some polling stations, saying they were assisting voters.

Further hurting Falcon's chances by splitting the anti-Maduro vote was a third candidate, evangelical pastor Javier Bertucci, who has picked up quite a following, not least thanks to his free soup handouts.

FIVE-YEAR RECESSION

Many Venezuelans are disillusioned and angry over the election: They criticize Maduro for economic hardships and the opposition for its dysfunctional splits.

Reeling from a fifth year of recession, falling oil production and U.S. sanctions, Venezuela is seeing growing levels of malnutrition, hyperinflation, and mass emigration.

"I'm telling the world: Stop your aggressive campaign against Venezuela," Maduro said as he voted, blaming opponents for the country's mess but giving no specifics of possible reforms to nearly two decades of state-led economic policies.

Venezuelan migrants staged small anti-Maduro protests in cities including Buenos Aires, Madrid and Miami. In the highland city of San Cristobal near Colombia, three cloth dolls representing loathed officials - electoral council President Tibisay Lucena, Socialist Party No. 2 Diosdado Cabello and Vice President Tareck El Aissami - were hung from a footbridge.

But streets were calm and for many Venezuelans, Sunday was a day to look for scant food or stock up on water, which is increasingly running short due to years of underinvestment.

"I'm not voting - what's the point if we already know the result? I prefer to come here to get water rather than waste my time," said Raul Sanchez, filling a jug from a tap by a busy road in the arid north-western city of Punto Fijo because his community has not had running water for 26 days.

State television urged Venezuelans to vote and Information Minister Jorge Rodriguez said some 2.5 million had voted by mid-morning, prompting ridicule from the opposition.

Some opposition supporters, however, say the boycott only made life easier for Maduro and that his rivals should have fought him at the ballot box despite an unfair playing ground.

"I'm voting because the opposition doesn't have any proposals for what we're going to do when Maduro wins today. I want this nightmare to stop," said teacher Luisa Marquez, 56, in Valencia.

Should Maduro win, he may choose to deepen a successful purge of critics within the ruling "Chavismo" movement.

Abroad, Maduro is likely to face further western protests should he win, although Russia and China remain allies and have been important financial backers.

Maduro faces a Herculean task to turn around the moribund economy with the bolivar currency down 99 percent in the last year and inflation at an annual 14,000 percent, according to the National Assembly. Multinational corporations are also departing or minimizing operations in Venezuela.

(Reuters Venezuela election coverage on Twitter @ReutersVzla)

(Additional reporting by Anggy Polanco and Brian Ellsworth in San Cristobal; Luc Cohen and Vivian Sequera in Caracas; Mircely Guanipa in Punto Fijo; Tibisay Romero in Valencia; Francisco Aguilar in Barinas; Maria Ramirez in Ciudad Guayana; and Caroline Stauffer and Hugh Bronstein in Buenos Aires; Writing by Alexandra Ulmer and Andrew Cawthorne Editing by Lisa Shumaker)

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