Mexican regional elections on Sunday pose a major test for the ruling party's hopes of retaining the presidency in 2018 as discontent over corruption and violence fuels support for the anti-establishment message of a resurgent leftist firebrand.
Voters were choosing new governors in a dozen of Mexico's 3 states, including bastions of President Enrique Pena Nieto's Institutional Revolutionary Party, or PRI, that could fall to the opposition after more than 80 years of one-party rule.
The biggest prize on offer is oil-rich Veracruz in the Gulf of Mexico, the third most-populous state, which has been long dominated by a few families under nonstop PRI government.
Initial exit polls by newspaper El Financiero showed the PRI's candidate Hector Yunes leading by a small margin in the state, trailed by his cousin Miguel Angel Yunes, who heads a joint bid by the main center-right and center-left opposition parties. Both Yunes said polls put them ahead.