El Salvador ? A conservative candidate has conceded defeat in El Salvador’s presidential vote to the party of former guerrillas, who have gained power for the first time since a bloody civil war ended 17 years ago.

Rodrigo Avila of the conservative Arena party says he recognizes the victory of Mauricio Funes of the Farabundo Marti National Liberation Front. He says he wishes him luck and plans to lead a formidable opposition.

Funes’ victory Sunday extends a string of leftist triumphs in Latin America at a time of uncertainty over how President Barack Obama will approach the region.

It ends two decades of conservative rule that have made El Salvador one of the staunchest U.S. allies in the region.