Conservative supermarket magnate Ricardo Martinelli won Panama's presidential election in a landslide May 3, promising to guide the country through the world economic crisis and an ambitious expansion of the Panama Canal.

The win by Martinelli, of the opposition Alliance for Change, marked a rare center-right election triumph in a region that has seen a wave of leftist leaders.

Electoral Tribunal President Erasmo Pinilla called Martinelli the "indisputable winner" after preliminary results with 87 percent of the votes counted showed him with 61 percent support and governing party candidate Balbina Herrera with 37 percent. Former President Guillermo Endara was a distant third.

The U.S.-educated, pro-business Martinelli, 57, who owns Panama's largest supermarket chain, said he would work for a national unity government.