A man wounded during an attack against Secretary of Labour and ex-prosecutor of Jalisco Luis Carlos Najera is assisted in downtown Guadalajara, Jalisco State, Mexico, on May 21, 201
(CNN)Even for a country numbed by escalating violence, the toll the campaign season in Mexico has exacted is horrifying.
In the nine months leading up to this weekend's presidential election, 132 candidates have been killed. That's according to a report by Etellekt, a risk analysis and crisis management firm.
The group's report, released Tuesday, found that 22 of Mexico's 32 states have seen a political assassination since campaigning began in September.
"These numbers anticipates a serious challenge of security for peace and democratic governance in these regions, and could debilitate the political party," the firm said.
One of the most shocking deaths occurred earlier this month when a congressional candidate was posing for a photo with someone. Fernando Puron had just left a debate in the northern state of Coahuila where he had vowed to tackle crime when a man walked up to him from behind and shot him the head.
Puron was a member of the Institutional Revolutionary Party, Mexico's main party. According to the Etellekt report, the party has lost 12 candidates to attacks -- the most deaths of all.
While the motives for these killings are unclear, drug cartels -- which operate in vast swaths of the country -- are believed to be behind many of them.
Many have criticized current President Enrique Peña Nieto, who took office December 1, 2012, for his inability to tame drug-related crimes during his time in office.
The killings highlighted in the analysis are part of a bigger pattern of attacks on candidates, Etellekt said. It counted 543 incidents, including kidnappings and extortion attempts.
But it's not just political violence that's spiking in Mexico. The country's homicide rate in 2017 was the highest on record, with more than 25,000 killings registered by the government.
And May 2018 was the deadliest month recorded in Mexico, since the government began releasing homicide data.
According to the government's most recent report, there has been a total of 20,506 homicides this year, with 4,381 homicides in May alone.
Election Day in Mexico is Sunday, when voters elect the country's new president and fill thousands of congressional, state and local seats. Peña Nieto cannot run for re-election because presidents are limited to one six-year term.