MEXICO CITY (AP) -- Mexico's left faces huge problems following the resignation of former presidential candidate Cuauhtemoc Cardenas, a pillar of progressive politics and son of the revered president who nationalized the oil industry.
In 1989, Cardenas founded the Democratic Revolution Party, known as the PRD. On Wednesday he said he is not only leaving the PRD, but party politics entirely.
Experts say Cardenas' resignation represents a blow to the party, but also frees it from the baggage of the past.
Cardenas is inextricably linked to his father Lazaro Cardenas and the old style of nationalist politics and state-run enterprises.
The left has been able to call thousands into the streets to protest the disappearance of 43 students in late September.
But the mayor implicated in those disappearances ran on the PRD ticket.