Reporting from Mexico City — Voting in the southern state of Yucatan on Sunday kicks off an election season in Mexico that is already shaping up as a hard slog for President Felipe Calderon and his conservative party.
Already, polls point to a possible near-sweep this year for the opposition Institutional Revolutionary Party, known as the PRI, as voters in about half the states pick state and local officeholders.
The slaying of a mayoral candidate from the president's National Action Party, or PAN, in northern Mexico on Thursday added to the sobering outlook.
Jose Mario Guajardo, who was running for mayor in Valle Hermoso in the violence-plagued northern state of Tamaulipas, was shot to death at his agricultural business, along with a son and an employee.
PAN leaders said Guajardo had been threatened, and the party's national president, Cesar Nava, said "all signs pointed" to the involvement of organized crime.
Even before the killing, PAN leaders said they were having trouble recruiting candidates in Tamaulipas, a PRI stronghold, because of fears of the drug-related violence that has increased there in recent months. Nava said the party would ask federal authorities to provide protection to other PAN candidates.
In Yucatan, where voters will choose 106 mayors and 25 state legislators, the most visible prize Sunday is the mayor's seat in the capital, Merida. The city has voted in favor of Calderon's PAN for 20 years, but analysts say there is a good chance it could swing to the PRI this time.
The campaign has been acrid, with PAN officials charging that Gov. Ivonne Ortega, of the PRI, has sought to rig the vote in favor of her party's mayoral candidate, Angelica Araujo. PRI officials deny the charges.
The PAN's candidate is Beatriz Zavala, who once served as Calderon's social development minister.
"If [PAN] loses Merida, it will be a serious blow," said Jorge Buendia, a Mexico City pollster.
Early polls also suggest an uphill battle for the PAN nationwide. The PRI leads in nearly all of the 12 states that will choose governors during a burst of state elections scheduled for July 4. It could take even the handful of states where Calderon's party has teamed with leftists to try to break the PRI's traditional lock on power in those areas.
A winning streak would further boost the surging PRI, which ran Mexico from top to bottom for seven decades until it fell to the PAN in 2000. Last year, the PRI regained control of the lower Chamber of Deputies. Mexico elects a new president in 2012, and early polls give the lead to Enrique Pena Nieto, the PRI governor of populous Mexico state.
Although the PRI lost the presidency in 2000 and was beaten again in 2006, it has remained a dominant force in the states and towns and cities across Mexico.
"The PRI seems to come back from the ashes, but the reality is that the PRI never really lost its various state bases," said Daniel Lund, an analyst based in Mexico City. "Its local apparatus of contact and clientism never was displaced."
Nine of the 12 states electing governors this year are already ruled by the PRI, lending an edge in campaigning since incumbent governors often use their authority to boost their party's candidates.
Calderon's party has been hurt by the economic crisis and drug-related violence that has worsened each year since 2006, when he launched a crackdown on drug traffickers soon after taking office.
In a recent poll by the Mitofsky firm, economic or safety-related issues accounted for the five worst problems. As the mood has worsened, support for the PRI has grown.
Guajardo is not the first local candidate to be slain amid the country's growing violence. Local officeholders, including mayors, have been targeted by drug-trafficking groups across Mexico.
Three state legislative candidates — from the PRI and the leftist Democratic Revolution Party — were slain during 2008 and last year.