Mexico holds a state election on Sunday that looks poised to bolster President Andres Manuel Lopez Obrador ahead of the race to succeed him, with his party forecast to capture the last major bastion of the country's old rulers.
The president's leftist National Regeneration Movement (MORENA) is expected to add the governorship of the State of Mexico to the 21 regional governments it already controls, two-thirds of the total.
The most populous region of the country, the State of Mexico surrounds much of the capital, and has been a major economic and electoral bulwark of the centrist Institutional Revolutionary Party (PRI), which has governed there since 1929.
Lopez Obrador routed the PRI to win the presidency in 2018, and MORENA has since absorbed most of the once-dominant party's strongholds, as well as many of its politicians.
Decades of one-party rule made the PRI a byword for corruption among many Mexicans, and it has struggled to compete with MORENA's message that it represents a vote for change.
A poll published this week by newspaper Reforma showed the gubernatorial race has narrowed, but still gave MORENA's candidate Delfina Gomez a 10 point-lead over Alejandra del Moral, a PRI politician fronting an opposition alliance.
"People are leaning towards Delfina because she seems like a new start, as with Lopez Obrador," said Jose Hernandez, a 64-year-old shopkeeper in Los Reyes Acaquilpan, a town in the eastern part of the state of 17 million people.
"Because in short, the whole of (the PRI) has been corrupt."
Gomez is vowing to give a fresh start to the state, and to improve security, mindful of widespread concern over violence. Del Moral says the PRI has learned from its mistakes and that her coalition will be a broader alternative to MORENA.
The vote comes a year before the next presidential election, with polls indicating MORENA will be very hard to beat then too.
In a separate election on Sunday, the PRI is forecast to maintain the northern border state of Coahuila, where splits inside MORENA produced rival left-wing candidates. MORENA this week sought to consolidate support in Coahuila by pressuring one of its national allies to abandon the renegade contender.
Lopez Obrador has dominated political life since taking office in December 2018, and his popularity, holding firm around 60%, has helped make MORENA a formidable electoral machine. Under Mexican law, presidents may only serve one six-year term.
Nevertheless, his abrasive style and uncompromising agenda, which has pitted the state against private enterprise, and fueled conflict with curbs on that power such as the judiciary, have also polarized voters.
Lopez Obrador has frequently criticized some sectors of middle class voters, and Mexico City and the State of Mexico in 2021 dealt MORENA unexpected setbacks in local elections.
Mexico City's mayor, Claudia Sheinbaum, has had a slight edge in most polling for the race to be MORENA's presidential candidate, pressed hard by Foreign Minister Marcelo Ebrard.
Sheinbaum, like Gomez, MORENA's State of Mexico candidate, is closely identified with Lopez Obrador and his agenda.
Failure to capture the State of Mexico, some analysts argue, could help make the case for putting up a presidential candidate with more moderate credentials such as Ebrard.
Because a MORENA victory has been taken for granted for months, an upset would give a powerful boost to the opposition, said Roy Campos, head of polling firm Consulta Mitofsky.
"For MORENA to lose this state," he said, "would basically mean getting off to a