WHAT’S AT STAKE: The closest presidential race in Mexican history. Ruling party candidate Felipe Calderon has an advantage of less than 0.6 percent, or about 240,000 votes, over leftist Andres Manuel Lopez Obrador.

THE REACTION: Lopez Obrador is asking Mexico’s top electoral court for a recount. He alleges widespread fraud; his supporters have set up protest camps in Mexico City.

THE RESPONSE: Calderon says the election was clean and fair. The Federal Electoral Court must declare a president-elect or annul the election by Sept. 6.

By The Associated Press