MORELIA, Mexico - Mexico's former ruling party won a major governor's race on Monday after a campaign marred by drug-cartel threats and violence, defeating President Felipe Calderon's sister and building momentum for its drive to take back the presidency next year.

Fausto Vallejo Figueroa of the Institutional Revolutionary Party, or PRI, won 35 percent of the vote in the western state of Michoacan. Luisa Maria Calderon took 33 percent, according to electoral authorities.

The president's sister implied that the PRI had been supported by drug gangs threatening her party's voters and poll watchers in retaliation for its aggressive stance against cartels. She said her team would carefully review vote tallies in parts of the state where they have received reports of armed men threatening people trying to vote.

"Allowing organized crime to manipulate elections will never lead to security," she said in an interview with the Televisa network.

The candidate for the leftist Democratic Revolution Party, which held the governor's seat, went further, explicitly alleging that the PRI has worked with cartels.

"The people of Michoacan won't let themselves be governed by a party with a history of pacts and agreements (with cartels), one that let organized crime coordinate the campaign," Democratic Revolution candidate Silvano Aureoles Conejo told Televisa.

The PRI's Vallejo responded that his backers were also subjected to criminal threats.

"No one was exempt," said Vallejo, who had been mayor of the state capital, Morelia.


The PAN was seeking a symbolic victory in Calderon's home state, where he launched the assault against cartels in late 2006. The drug war has killed more than 40,000 people according to many estimates, although no official figures have been released in nearly a year.

The National Action mayor of the city of La Piedad was gunned down as he handed out campaign literature for Calderon and other candidates less than two weeks before Sunday's election. On the day of the vote, a newspaper in the city published an unsigned note threatening supporters of the party known as the PAN and blaming it for deaths in the wake of its military-led offensive against drug cartels.

"Don't wear T-shirts or PAN advertising because we don't want to confuse you and have innocent people die," read the note, which was also circulated by email. News reports said the newspaper had been forced to publish the warning.

Yet the city's voters shook off the threat. The PAN candidate got 53 percent of the vote.

The win for the PRI is a major step toward regaining the presidency it lost in 2000 after governing Mexico for 71 years. Most polls show the PRI's Enrique Pena Nieto, former governor of Mexico State, leading the presidential race.

The biggest blow was to Democratic Revolution, which had wrenched the state away from the PRI in 2001 and built it into a stronghold. Aureoles trailed with 29 percent and the party lost control of the state legislature, where the PRI won 11 seats, Democratic Revolution eight and PAN five.

The state, a major producer of marijuana, opium and methamphetamines, has suffered dozens of drug cartel-related attacks on local officials over the past two years. Parts are controlled by the Knights Templar a pseudo-religious drug gang known as a major trafficker of methamphetamine. The remnants of the cult-like La Familia cartel also maintain a presence.

Luisa Maria Calderon campaigned on a promise to advance her brother's anti-drug campaign and led in most opinion polls going into the vote. The PAN has been hurt by a tepid economy and by voter fatigue over drug violence, a factor that also weakened Democratic Revolution.

As Michoacan's governing party for a decade, the leftist party drew criticism for the state's drug violence, and some of its legislative candidates also were accused of close ties to drug cartels.

National Action's vote total was stable from 2006 to 2011; Calderon's sister got about the same number of votes for governor as he did for president, and both lost in the state.

Voters switched by the hundreds of thousands from the PRD to the PRI. That's especially crucial because the PRD had largely taken over the old PRI grassroots machine in the state, which was the home base of the PRD's founder, Cuauhtemoc Cardenas, and one of the party's chief bastions.

Residents of the rural city of Cheran refused to let poll workers into their town, demanding an election they said would respect their customs and traditions. The indigenous Purepecha people who live in Cheran have in recent months wielded rifles and mounted roadblocks to keep out illegal loggers and drug traffickers.

The Michoacan Electoral Institute said in a news release Sunday that officials were still unable to carry out elections in Cheran and were determining how the 16,000 residents there will elect their leaders.

Twitter users claiming to belong to the "Anonymous" hackers movement said they were behind an attack on the website of a party backing Luisa Maria Calderon. The tweets also said hackers attacked the Michoacan Electoral Institute's website.