In Uruguay, socialist leader Tabare Vazquez is claiming victory in a landmark presidential election, and his coalition supporters appear to be making big gains in Congress, signaling a historic shift to the left for the South American nation.
Mr. Vazquez's closest competitor, Jorge Larranaga, conceded defeat late Sunday, after exit polls indicated Mr. Vazquez had over 50 percent of the vote - enough to win the presidency outright and avoid a runoff vote.
Mr. Vazquez's Broad Front coalition - including socialists, communists, Social Democrats and a popular former guerrilla group, Tupamaros - also appeared to be heading for big gains in both houses of Congress.
Official results were expected later Monday.
Mr. Vazquez, an oncologist and former mayor of the capital Montevideo, is the latest in a series of leftist leaders winning national elections in South America, including Brazil, Argentina, Chile and Venezuela.
Uruguay's shift to the left comes at the expense of the country's traditional Colorado and National parties, which many voters blamed for recent years of economic crisis, as well as decades of corruption and cronyism.
If the predicted election results are confirmed, they would mark the Colorado and National parties' first electoral defeat. Apart from relatively brief periods of military rule, the two traditional parties have alternated in power ever since Uruguay gained its independence from Spain in the early 19th century.
Regional elections also were held in Venezuela Sunday. Preliminary results indicate supporters of left-leaning President Hugo Chavez won all but two of 23 governorships.Some information for this report provided by AP, AFP and Reuters.