 The Civic Union established a presidential ticket with Bartolomé Mitre and Bernardo de Irigoyen.However, Julio Argentino Roca, undisputed leader of the pro-government National Autonomist Party, made a deal with Mitre to form a "national unity" ticket headed by Mitre.After learning of the arrangement on April 16, Leandro Alem opposed it emphatically, splitting the Civic Union and forcing Mitre to abandon his candidacy.