Traditionally weak here, the PRD gambled on nominating a so-called citizen candidate, Polevnsky, 47, a former chamber of commerce vice president with little political experience. Her weak rapport with local voters and less than stirring stump presence disenchanted voters. She was also forced to explain that she had changed her name because she had been raped by a family member at the age of 12.
Polevnsky's weak finish also reflected poorly on Mexico City Mayor Andres Manuel Lopez Obrador -- the front-runner in preference polls for next year's presidential race -- who made several campaign appearances in her behalf.
"It may be indicative of the fact that Lopez Obrador doesn't have much influence beyond Mexico City if in a neighboring state he is not able to give his candidate any lift whatsoever," said Armand Peschard-Sverdrup, head of the Mexico Project at the Center for Strategic and International Studies, a Washington think tank.
Fox was chastised for appearing at a Saturday rally at the Angel of Independence monument in Mexico City to celebrate the fifth anniversary of his victory over the PRI.
Mexican law forbids the president to participate in any campaign activity.
Fox insisted that the celebration was not intended to back a specific candidate. But many questioned the timing of the event, coming on the eve of the crucial state election, and noted that the so-called Democracy Celebration Day had never been observed before. Fox ignored an appeal from the Federal Electoral Institute urging that he not attend.