The campaign for Mexico's July 1 presidential election officially opened Friday, with Andres Manuel Lopez Obrador, a veteran leftist promising a sharp break with the past, positioned as the man to beat.
"AMLO," as he is widely known, has a double-digit lead at the start of the race to succeed President Enrique Pena Nieto, whose popularity has been flayed by corruption scandals, a seemingly hopeless war on drug cartels and record-shattering crime that has left a trail of bodies in its wake.
But Lopez Obrador, a sometimes fiery leftist who is making his third presidential bid, has been here before: in 2006, he led for most of the race, then narrowly lost to Felipe Calderon of the conservative National Action Party (PAN).
Two rivals are meanwhile fighting a no-holds-barred battle for second place.
Ricardo Anaya of the PAN is a youthful ex-lawmaker whose bid to campaign as a fresh face has been blotched by accusations of corruption and strongarming his way to his party's nomination.
Jose Antonio Meade is a respected former finance minister standing for the ruling Institutional Revolutionary Party (PRI) -- a long-dominant force in Mexican politics whose popularity is now so low it tapped a non-party member as its candidate.
Running a distant fourth is independent Margarita Zavala, ex-president Calderon's wife, who quit the PAN in a bitter dispute with Anaya and is now peeling away a potentially crucial part of his vote.
Anaya and Zavala kicked off their campaigns with midnight rallies in Mexico City. Lopez Obrador and Meade are saving their first big rallies for Sunday -- Easter, a date charged with symbolism in this still very Catholic country.
All hope to draw mega-crowds that day to boost their momentum.
Anything remains possible in the single-round vote, but AMLO looks ever harder to beat, said Mexican political analyst Jose Antonio Crespo.
"We can't rule anything out. In other elections we've seen how things can change in the final months. But it's looking difficult" to beat Lopez Obrador, he told AFP.
"There's an open war between the PRI and the PAN.... They're hitting each other so hard they're both falling down, leaving Lopez Obrador a wide-open path to victory."
- Own worst enemy? -
Recent polls give Lopez Obrador just over 40 percent of the vote, with Anaya and Meade in the 20s and Zavala in single digits.
But it is often said in Mexico that "AMLO's worst enemy is AMLO."
Detractors say the former Mexico City mayor harbors a radical, intolerant and messianic side that scares most voters whenever he lets it surface.
Famous for railing against Mexico's "mafia of power," Lopez Obrador, 64, has so far struck a light, humorous tone during a months-long "pre-campaign," joking that he is all "peace and love" in 2018.
But he has recently ventured into more controversial territory, with talk of reversing Pena Nieto's landmark privatization of the energy sector, abandoning construction on a new $13-billion airport for Mexico City, restarting from scratch on negotiating an updated NAFTA trade deal with the United States and Canada, and an amnesty for drug traffickers.
Anaya and Meade are meanwhile locked in an ugly brawl.
Meade, 49, has hit out relentlessly at Anaya for an investigation into his family's $2.95-million sale of an industrial property in a suspected money-laundering scheme.
Anaya, 39, who is not under investigation himself and denies any wrongdoing, says the ruling party fabricated the case to hurt him, and accuses Meade of abetting the corruption rotting the political system.
- 'Disgusted with politics' -
Mexico's president for the next six years will inherit a lackluster economy, the blood-stained war on drugs and touchy ties with key trading partner the United States under President Donald Trump.
Voters are hungry for change, but in a country with a long history of cronyism and corruption in politics, there is no true outsider candidate, said Pamela Starr, a Mexico specialist at the University of Southern California.
Even Lopez Obrador has been in politics since the 1970s, she pointed out.
"Mexicans are disgusted with parties and politicians... but there are no outsiders because the political system won't permit outsiders," she said.
"All four candidates have been part of the political system their entire lives."