Ecuador's president Rafael Correa has been elected to a third term in power.

The leftwing incumbent, who first took office in 2007 and was re-elected in 2009, won 58% of the vote, well ahead of his closest challenger, former banker Guillermo Lasso, with 24%.

A beaming Correa appeared on state TV hugging jubilant supporters at the Carondelet presidential palace less than an hour after polls closed. "This victory is yours. It belongs to our families, to our wife, to our friends, our neighbours, the entire nation," Correa said. "We are only here to serve you. Nothing for us. Everything for you, a people who have become dignified in being free."

The 48-year-old Correa has raised living standards for the lower classes and widened the welfare state with region-leading social spending but critics including international human rights groups call him a bully.

Correa has brought uncharacteristic political stability to the oil-exporting nation of 14.6 million people that had been through seven presidents in the decade before him.

To avoid a runoff, Correa needed a simple majority or 40% of the vote plus a 10-point margin over the runnerup.

Correa has endeared himself to the poor and lower middle class by making education and health care more accessible, building or improving roads and creating 95,400 jobs in the past four years, according to government figures.

But Correa's critics say his "citizens' revolution" has been accompanied by his arbitrary wielding of a near-monopoly on state power against anyone who threatens it.

Correa has eroded the influence of opposition parties, the Roman Catholic church and the news media and used criminal libel law to try to silence opposition journalists.

The US-educated Correa gained an early reputation as a maverick, defying international financiers by defaulting on $3.9bn in foreign debt obligations and rewriting contracts with oil multinationals to secure a higher share of oil revenues for Ecuador.

He has also kept the United States at arm's length while upsetting Britain and Sweden in August by granting asylum at the Ecuadorean embassy in London to WikiLeaks founder Julian Assange, the online spiller of leaked US government secrets who is wanted for questioning in Sweden for alleged sexual assault.