Feb. 19 (UPI) -- Three presidential candidates accepted the nominations of Mexico's main political parties, kicking off the July 1 race to succeed President Enrique Peña Nieto.
Lopez Obrador promised sweeping change for Mexico if he were elected.
"I'm aware of my historic responsibility. I want to be remembered as a good president," he told supporters in Mexico City. "I'm stubborn. It's a well-known fact. With that same conviction, I will act as president ... stubbornly, obstinately, persistently, bordering on craziness, to wipe out corruption."
Ricardo Anaya, who is running with the conservative National Action Party, said he won't allow Trump to treat Mexico like a "doormat."
"No more will we turn ourselves into doormats before the U.S. government the way this federal government has done," Anaya said.
Speaking Sunday at a campaign event in Mexico City, Anaya said he wouldn't pay for Trump's promised border wall and declared the violence in Mexico is due to U.S. demand for drugs.
Jose Antonio Meade is running in Nieto's party, the Institutional Revolutionary Party (PRI).
Polls show Lopez Obrador with little over 30 percent of the vote while Anaya and Meade are in the 20 percent and less than 20 percent range, respectively.
Mexico's next president will deal with a struggling economy, a corrupt political system and ongoing violence with the country's powerful drug cartels.