Andrés Manuel López Obrador won a landslide victory Sunday in Mexico's presidential election, handily defeating rivals from the Institutional Revolutionary Party (PRI) and the National Action Party (PAN).

"This is a historic occasion," said Indiana University history professor Peter Guardino, whose research focuses on Mexican history. "López Obrador has won the largest percentage of votes by any presidential candidate since Mexican elections were democratized 20 years ago. Moreover, the PRI, which dominated Mexican politics for many decades, received very few votes. More than anything the public has lost faith in the ability of the PRI and its rightwing rival, the PAN, to govern. Widespread corruption, criminal violence and continued poverty for almost half the population doomed the political establishment."

While López Obrador promised increased prosperity and an end to corruption, expectations of change should be tempered, Guardino said.

"Under Mexico’s Constitution, the presidency is not very powerful," he said. "Most likely López Obrador will act as president much as he acted when he was mayor of Mexico City. He will try to involve Mexico’s middle classes and wealthy in his project to raise the incomes of the poor, working to show them that a more equitable and prosperous Mexico is good for everyone."

To speak with Guardino, contact Steve Hinnefeld at 812-856-3488 or