Mexico City ? For most of the world, Mexico will inaugurate a president named Felipe Calderon this morning. Congratulations will flow from around the globe. Cabinet members will be sworn in. Mariachi music will play.

It won’t change a thing, however, in the bright yellow building at 64 San Luis Potosi St. Inside sits the man who insists that he’s the real president of Mexico: Andres Manuel Lopez Obrador, who has his own Cabinet, his own budget and even his own tricolor presidential sash, which he strapped on more than two weeks ago.

“Office of the legitimate president,” his aides say when answering the phone. Never mind that he lost at the ballot box and in the courts.

Welcome to the alternate reality that Lopez Obrador has carved out months after the country’s highest electoral court declared that he’d lost the July presidential election by some 230,000 votes, the most closely contested presidential race in Mexico’s history.

His most ardent supporters, convinced that the election was stolen from them, seem ready to follow the fiery leftist anywhere. But others say they hardly recognize Lopez Obrador anymore, describing a haunted and lonely man consumed by the passion that he once called the “Achilles’ heel” of ambitious politicians from his native state of Tabasco, in Mexico’s deep south.

“He has taken on a messianic attitude,” said Alejandro Almazan, the author of a recent book on Lopez Obrador’s unsuccessful campaign. “I don’t know what happened, but he is not the man I used to know.”

Is the “legitimate presidency” all a game or a pre-campaign for the 2012 presidential race, as some suggest? Without tapping into Lopez Obrador’s thoughts, it’s impossible to say. He rarely grants interviews and refused a request this week from McClatchy Newspapers.

But he told the newspaper El Noroeste this week that he’s not play-acting.

“I already am the legitimate president of Mexico, proudly so,” he said when he was asked whether he’d run again in 2012. “We are going to govern with the participation of the people.”

His Cabinet “secretary” of political affairs, Jose Agustin Ortiz Pinchette, sounded a more conciliatory note in an interview with McClatchy on Thursday.

“We’re not living in an imaginary world,” he said. “We know that Calderon is going to establish a de facto government … that is a reality.”