2006 Mexican presidential election dispute
Felipe Calderón defeated Andrés Manuel López Obrador by less than one percentage point. López Obrador claimed fraud and led protests that shut down Mexico City's Reforma avenue for weeks, with supporters camped in the Zócalo.
The Federal Electoral Institute certified Calderón's victory despite the protests.
The episode fueled calls to overhaul electoral institutions, which produced the 2014 reform that created the INE.
Shows what happens in Mexico when a major political force challenges an election's integrity: the institution organizing the vote takes lasting damage.
