Their exiled leader, Juan Perón had given President Arturo Frondizi a critical endorsement in 1958; but Frondizi's inability to lift the ban on Peronism had led Perón to support proxy political partes organized after his overthrow, notably Juan Atilio Bramuglia's Popular Union.

The Popular Union nominated textile industry workers' leader Andrés Framini for governor of the Province of Buenos Aires (home to 38% of Argentines) and for vice-governor: Perón, himself.

The leader believed this symbolic spot on the ticket (which, unable to return, he could never fill) would prove a powerful endorsement to Framini; but the move backfired when Frondizi was forced to declare Perón's candidacy null and void.

The clear reference to the Casa Rosada (the president's executive office building) put anti-peronists and the military on high alert when, in fact, Perón's proxies won 10 of 14 governorships at stake - including Framini's victory in the all-important Province of Buenos Aires.

Guido, a member of Frondizi's UCRI, reluctantly accepted the figurehead post and on May 1, annulled the results of all legislative and gubernatorial 1962 elections.