For months Enrique Pena Nieto has enjoyed a commanding lead in the polls in the run-up to Mexico's presidential election on July 1.
"[It] suddenly seems like the inevitability of his [Pena Nieto's] election is not so clear and without a doubt, the role of the students has been an important factor ... because it's been spontaneous, it's not been controlled by other parties, it's viewed as an expression of general public sentiment against a conglomerate of a news media."
- Eric Olson from the Mexico Institute at the Woodrow Wilson Center
Pena Nieto has benefited from widespread discontent over the way President Felipe Calderon's National Action Party (PAN) has governed Mexico, with their candidate, Josefina Vazquez Mota, floundering in the polls.
But thousands took to the streets on Sunday in protests against Pena Nieto organised by the student-led 'I am 132' movement. They oppose a return to power of his Institutional Revolutionary Party (PRI), whose 71-year rule of the country up until 2000 was marred by corruption and authoritarianism.
Pena Nieto has also been damaged by allegations that the country's main broadcaster, Televisa, had colluded with his party to favour his candidacy.
It is the candidate of the left, Andres Manuel Lopez Obrador of the Party of the Democratic Revolution (PRD), who narrowly lost out to Calderon in 2006, who could benefit from any backlash against Pena Nieto.
In recent weeks, Lopez Obrador has been gaining ground in the polls.
But whoever wins this election will have to grapple with a country ravaged by drug violence and poverty.
The candidates clashed in Sunday's final presidential debate although none of them managed to land a knockout blow.
"The majority of people ... have a sense of uncertainty. There's a high percentage of distrust, the system is not trusted. And currently, pollsters in Mexico are undergoing an existential crisis .... There are [a] couple of really reputable pollsters who have come out with results that in fact look lopsided and so suddenly these things coming from credible sources have made everyone really start having doubts."
- Francisco Gonzalez, a professor at John Hopkins University
The two main topics that dominated the debate were corruption and the economy. But what was once again glaringly absent were concrete proposals from the candidates to fight the drug violence that has claimed more than 50,000 lives in the past five years.
So where do the parties stand following that debate?
The most recent polls out of Mexico have shown mixed results.
A poll conducted by the newspaper Reforma put support for Pena Nieto at 29 per cent, Lopez Obrador at 26 and Vasquez Mota trailing with 18 per cent.
This poll gives Pena Nieto a slim three per cent lead, significantly lower than the lead just a month ago, when Pena Nieto led Lopez Obrador by 11 per cent.
But another recent poll had Pena Nieto on 33 percent - a commanding 12 point lead over Lopez Obrador's 21 percent - and Vazquez Mota in third place at 20 per cent.
As Mexico's presidential race enters its final weeks, we ask: Who is going to win the Mexican election? And can anyone stop Enrique Pena Nieto being elected the country's president?
Inside Story Americas, with presenter Shihab Rattansi, discusses with guests: Maria Jose Lopez, a spokesperson for the 'Yo Soy 132' or 'I am 132' student movement; Eric Olson, a senior associate at the Mexico Institute at the Woodrow Wilson Center; and Francisco Gonzalez, a professor of Latin American studies at John Hopkins university.
"We are trying to achieve lots of things ... first of all it was against the biased media coverage. It was a stand that we took in our video ... when we said we are not going to let media outlets, we are not going to let members of political parties lie openly to us."
Maria Jose Lopez, a spokesperson for the 'I am 132' student movement