Mexico City, Jul 26 (EFE).- Leftist Andres Manuel Lopez Obrador told the biggest Spanish-language television network in the United States that he is president of Mexico "by the will of the majority," though election authorities have yet to rule on his challenge of results that gave the victory to his conservative opponent. Officials results showed Felipe Calderon with an advantage of 0.58 percent over Lopez Obrador in the July 2 balloting, but the leftist is demanding a vote-by-vote recount. Mexico's electoral tribunal has until Sept. 6 to declare who will be sworn-in Dec. 1 to succeed conservative incumbent Vicente Fox...