But those very proposals, especially on the oil industry, have drawn the leftist Democratic Revolution Party, the PRD, into the streets for angry protests in the past.
Lopez Obrador, the PRD's candidate, refused to concede the election.
"We can't accept a fraudulent result," he told supporters Monday evening, a reference to his allegations that Pena Nieto exceeded campaign spending limits, bought votes in some states and benefited from favorable coverage in Mexico's semi-monopolized television industry.
Lopez Obrador said he will likely challenge Sunday's vote results, but didn't say if he would try to repeat nearly two months of street blockades in Mexico City that he led in 2006 to protest a narrow loss to Calderon that he attributed to fraud.
Lopez Obrador's party actually did better in this election than polls had projected, winning apparent victories in three of the seven state elections Sunday. The PRD was on track to win an overwhelming victory in Mexico City, the nation's capital and largest city, as well as taking the governorships of Morelos state to the south and the Gulf coast state of Tabasco, both of which were held by other parties. The PRI appeared to have taken the governorship of the western state of Jalisco from the National Action Party.
Despite winning the presidency, the PRI may actually lose seats in Congress. The PRI-led coalition with the Green Party had about 38 percent of the congressional vote, with 95 percent of ballots counted Monday. The coalition won about 46 percent in the last legislative vote three years ago.
Many Mexicans questioned why most pre-election polls underestimated support for Lopez Obrador by five or six percentage points, well outside those polls' margin of error. Lopez Obrador had claimed the polls were being manipulated, an accusation that accompanied frequent complaints that Pena Nieto was running a far more expensive campaign than his rivals.
Jorge Buendia of the polling firm Buendia and Laredo said some people who said they would vote for Pena Nieto appeared to have changed their minds. There was also a surge in support for Lopez Obrador in the final days that couldn't be fully measured because Mexico's electoral law effectively prohibits polling in the last week before elections.
The PRI's victory appeared to be, above all, a triumph of pragmatism and power-broker politics. Few of those at Pena Nieto's victory rally Sunday expressed the high-flown rhetoric about democratic transition and reform that were popular when National Action won the 2000 and 2006 elections. For its decades in power, the PRI excelled at handing out patronage jobs as well as work and business permits in exchange for votes.
Jaime Bernal, 48, who works as an aide to a PRI congressman, said at the rally that the secret to the party's comeback was recognizing "the important thing for people is that they have something to eat, a job to support themselves."
But he also praised Pena Nieto's ease at working crowds, shaking hands and hugging people, a talent the party had lost during two decades of PRI presidents known as market-oriented "technocrats."
Associated Press writer Olga R. Rodriguez contributed to this report.