Ortega won with 38 percent of the vote, 9 points ahead of his Washington-backed conservative rival Eduardo Montealegre.

Ortega, who seized power in a popular 1979 revolution and fought US-backed Contra rebels as president in the 1980s, was conciliatory in victory but the White House warned its support for Nicaragua would hinge on his commitment to democracy.

The 60-year-old president-elect met Montealegre late on Tuesday and both promised to work together to attack poverty and encourage the private investment needed to create jobs.

"We thank God for this chance to build a Nicaragua in reconciliation by talking to each other and reaching consensus, even with our differences," Ortega said.

His victory in a third comeback attempt was a huge boost for Venezuelan President Hugo Chavez, who is trying to build a Latin American alliance of anti-US leaders.

The two friends spoke by telephone on Tuesday night and Ortega said he was sure Chavez would be re-elected next month.

"I'm convinced that, as we have won today, our Venezuelan brother will have a new victory on December 3 and continue the struggle for justice, peace and solidarity between peoples," he said in a chat broadcast on Venezuelan state television.

"Latin America is leaving forever its role as the backyard of the North American empire. Yankee go home! Gringo go home! This land is ours, this is our America!" a delighted Chavez had said.