MEXICO CITY -- Political assassinations, kidnappings and threats have cast a pall over upcoming regional elections in which the ruling party is stressing its efforts to control violence as it seeks to consolidate power.
Authorities reported that a mayoral candidate in Durango state was shot to death Monday by unknown assailants, his body dumped on a roadside, after he had been kidnapped at a funeral.
Over the weekend, gunmen pumped more than 25 rounds into a car carrying Rosalia Palma, a candidate for state legislature in Oaxaca. Her husband and niece, who worked on Ms. Palma's campaign, were killed and the candidate wounded. On June 12, a candidate for mayor in Chihuahua state was slain by armed men who seized him from his home.
Other mayoral and local legislative candidates as well as party officials have reported being attacked, their homes being shot up or receiving threats in the run-up to Sunday's elections in 14 states. Victims have come from all of the major political parties.
The elections correspond to roughly a third of the Mexican electorate and are the first to take place since Enrique Pena Nieto led his Institutional Revolutionary Party, or PRI, back to the presidency in December after a 12-year hiatus. The PRI had previously ruled virtually unchallenged for seven decades.
One major exception to the PRI's long rule was the state of Baja California, which in 1989 elected a governor from the conservative National Action Party, or PAN, the first time in modern Mexican history that an opposition party took a state's highest office.
The PAN has controlled the Baja statehouse ever since. But polls indicate that the PRI may finally regain the long-elusive post Sunday, when voters select a governor in the state bordering California. It would be a major blow to the PAN, which is reeling from a series of electoral defeats and imploding amid internal power struggles.
Violence typically surges before elections in Mexico, but the recent incidents seem to be part of a wider wave of killings, kidnappings and other crimes that challenge the government's claims to have improved security since returning to power.
A leading civic group released a report last week that showed that kidnappings, far from decreasing, have soared to the highest level in years. Mr. Pena Nieto has placed a stronger emphasis on reducing crime, including killings and kidnappings, than on fighting drug cartels. His government vigorously disputed the group's findings.
The organization, the National Citizens Observatory for Security and Justice, said homicides were declining slightly, continuing a trend that started a year and a half ago, and other major crimes had also dropped.
A survey released Tuesday by the state statistical institute said the public's perception of safety improved in June compared with the same month last year. But the survey also showed that public confidence in security, while not as low as in 2012, has steadily declined since December.
Some experts say any public perception of improvement has less to do with real peace and more to do with the government's decision to discourage the reporting or publicizing of violent acts.
Election-season violence comes from drug-trafficking gangs seeking to control elected officials as well as local political bosses who also seek to strong-arm candidates and buy off voters.
The violence nationwide has been accompanied by a rash of corruption scandals and bitterly traded accusations over alleged vote-buying schemes and illegal spending.
The government, meanwhile, promised to make Sunday's vote safe. Cesar Camacho, national president of the PRI, said that all major parties "unanimously asked" for special security and that additional police would be deployed in all states holding elections.