Disputed Calderón vs. López Obrador Election — AMLO Claims Fraud

Felipe Calderón (PAN) won the 2006 presidential election by just 243,934 votes (0.58%) over Andrés Manuel López Obrador (PRD). AMLO refused to accept the result, set up a 'parallel government' in Mexico City's Zócalo for months, and declared himself 'legitimate president.' The TRIFE (Federal Electoral Tribunal) upheld Calderón's victory after a partial recount, finding irregularities but not enough to change the outcome. The episode deepened Mexico's political polarization and set AMLO on his path to a third presidential bid.