Mexicans lined up to vote for a new president on Sunday in an election tipped to hand power to an anti-establishment outsider who would inject a new dose of nationalism into government and could sharpen divisions with US President Donald Trump.

Andres Manuel Lopez Obrador, a former Mexico City mayor, has led opinion polls throughout a campaign marred by more than 100 murders of politicians by suspected drug gangs.

Lopez Obrador would be the first leftist to become president in decades in Mexico, Latin America’s No. 2 economy, if he ousts the ruling centrist Institutional Revolutionary Party (PRI).

Runner-up in the 2006 and 2012 elections, Lopez Obrador pitches himself as the only man capable of cleaning up a political class whose credibility has been ground down by persistent graft, soaring crime levels and years of subpar economic growth.

“We are tired of so much corruption,” said Jose Alfredo Ortiz, a 32-year-old shopkeeper who planned to vote for Lopez Obrador in the gritty Mexico City suburb of Ecatepec. What people want is a change, somebody who will govern differently.”

The law bars current President Enrique Pena Nieto from seeking re-election. His popularity crumbled as his name became tainted by investigations into alleged conflicts-of-interest and embezzlement scandals engulfing top PRI officials.

“The new president of Mexico will have moral and political authority to demand everyone behaves with integrity and make honesty a priority as a way of life,” Lopez Obrador said in his campaign finale in a soccer stadium in the capital on Wednesday.

Campaigning relentlessly around Mexico for the past 13 years, Lopez Obrador has watched political careers rise and fall as established parties were consumed by the country’s social and economic problems and the responsibility of power.

Lopez Obrador, 64, has been vague on policy details. Seeking to harness support from economic nationalists, leftist liberals and social conservatives, he vows to reduce inequality, improve pay and welfare spending, as well as run a tight budget.

A vocal opponent of the government’s economic agenda, his criticism has been tempered by business-friendly aides.

But he has played with the idea of referendums to resolve divisive issues like whether to continue with Pena Nieto’s opening of the oil and gas industry to private capital.

His rivals Ricardo Anaya, an ex-leader of the center-right National Action Party (PAN) heading a right-left alliance, and PRI candidate Jose Antonio Meade, a former finance minister, differ only in nuance in their support of the energy reform.

Their efforts to catch Lopez Obrador have been hampered by attacks on each other, allowing him to build a lead that some opinion polls have put in excess of 20 percentage points. They also represent the only two parties to have ruled modern Mexico.