IT IS one of the lasting images of Mexico’s election campaign: as a Congressional candidate poses for a selfie with a supporter, a man in a baseball cap calmly approaches and shoots him in the back of the head.

Fernando Puron, who was running for Congress in the northern state of Coahuila, is one of 136 politicians murdered since candidate registration for Sunday’s elections in Mexico opened in September, according to the consulting firm Etellekt.

It is by far the bloodiest Mexican campaign on record, as the violence gripping the country has exploded massively into the political world.

media_camera Fernando Puron, a politician who promised to crack down on the cartels, was shot dead while taking a selfie on the campaign trail. Picture: YouTube

Mr Puron, 43, had just left a June 8 debate — in which he had vowed to crack down on drug cartels, citing his record fighting the brutal Zetas cartel as mayor of the city of Piedras Negras — when he stopped outside to pose for a picture with a supporter.

Grainy footage from a security camera shows how another man watched the pair from a distance, then walked up to Puron, put a gun to the back of his head, and pulled the trigger, walking off as the candidate crumpled to the ground.

He is one of 48 candidates murdered this campaign season — 28 who were killed during the primary campaigns and 20 during the general election campaign, according to Etellekt.

At the last national elections, in 2012, nine politicians and one candidate were murdered.

media_camera Policemen patrol the streets of Mexico City on June 29, 2018, ahead of the July 1 presidential election. Picture: AFP Photo/Johan Ordonez

The new figure shows the lengths to which the country’s powerful drug cartels are going to place their own allies in local government, in a bid for territory, government resources and soft policing, analysts say.

The new law of local politics in Mexico is that “you have to obey orders from the hitman or capo” who rules your turf, said consultant Luis Carlos Ugalde, former head of Mexico’s federal electoral authority.

“If they think a politician’s not going to work with them, negotiate, back down, then they kill him,” he told AFP.

media_camera Mexican Navy marines patrol in Mexico City on July 16, 2013. Picture: AFP Photo/Yuri Cortez

This political violence is part of the larger bloodbath harrowing Mexico, which has left more than 200,000 people murdered since the government deployed the army to fight the cartels in 2006.

That includes a record 25,339 murders last year.

Violence is a major issue in the campaign, and one that has hit hard across the country — whether in the chic resort region of Los Cabos, on the Baja California peninsula, or in places mired in the poverty that affects more than 50 million of Mexico’s 120 million people.

media_camera Words written in blood on the walls of a house next to the bodies of 26 men and two women in a farm in La Libertad on the Mexico border, allegedly were shot dead and beheaded by the Zetas cartel. Picture: EPA/STR Guatemala Out

The country has grown used to seeing burned and mutilated bodies abandoned on highways, police and soldiers attacked by heavily armed hitmen, or headless bodies floating in rivers.

It is often hard to decipher why a given politician was killed.

Some, like Puron, appear to have been eliminated for fighting the cartels. Others appear to have been taken out for striking a deal with a rival cartel, and still others have been killed in crimes that, like so many in Mexico, remain murky.

“We should be asking ourselves how many candidates are being murdered because they’re mixed up in organised crime. That’s the major problem,” said Mr Ugalde.

The director of Etellekt, Ruben Salazar, is critical of the “failed” strategy of the government’s drug war, which has only fragmented the cartels, he said.

media_camera A military patrol drive past a political propaganda banner for Laura Caballero, a candidate for the Guerrero state legislature. Three years ago Caballero closed her restaurant in Acapulco after organised crime tried to extort her. Picture: AP Photo/Marco Ugarte

“An infinitude of criminal cells emerged, and now they are waging a constantly escalating battle for control of territory and trafficking routes,” he said.

Sergio Aguayo, a security expert at El Colegio de Mexico, said the country faces a deep-rooted problem of “complicity between public officials and criminals.” That poses a severe problem for Mexican democracy, regardless of how Sunday’s elections turn out.

“I can’t think of another country in the world where organised crime has achieved as much power as it has in Mexico,” Mr Aguayo said.

Mexico’s Journalists Are Targets, Too

It can be deadly to ask questions about multibillion-dollar drug cartels or government corruption in Mexico, where more than 100 journalists have been murdered since 2000.

Ninety percent of those cases remain unsolved.

At least six journalists have been murdered in the country so far this year:

Carlos Dominguez, 72, was attacked as he drove in his car with his son, daughter-in-law and two grandchildren on January 13.

His attackers broke the driver’s side window and stabbed him 21 times, according to police.

In his last column, Dominguez condemned the violence sweeping Mexico in the buildup to the country’s July 1 elections.

media_camera Relatives of Mexican journalist Carlos Dominguez Rodriguez, murdered on January 13, attend his funeral. Picture: AFP Photo/Francisco Robles

Pamela Montenegro, 36, a video blogger on YouTube, was shot dead by gunmen inside a restaurant she owned in Acapulco on February 5.

Leobardo Vazquez, 42, was gunned down on March 21 outside his home in the eastern state of Veracruz, the deadliest for journalists in Mexico.

Juan Carlos Huerta, 45, a radio and television journalist, was shot dead on May 15 as he left his home in a suburb of Villahermosa.

Hector Gonzalez, 40, a news correspondent for national daily, was found beaten to death on a dirt road.

Jose Guadalupe Chan, 35, a reporter for a digital weekly, was was shot dead by an unknown assailant at a bar.

A colleague said that Chan told him he had received threats and sought protection from authorities but did not get a response.

Originally published as Mexico’s bloodiest election year