The party's candidate Ricardo Jiménez Oreamuno was elected president in 1910.

[2] After electing Jiménez on three occasions, the party also secured the election of León Cortés Castro in 1936, Rafael Ángel Calderón Guardia in 1940 and Teodoro Picado Michalski in 1944 becoming a dominant party.

During Calderón's leadership the party moved toward Christian democracy and Christian socialism making some of the country's first social reforms in alliance with the Communist Party.

Criticism over corruption, authoritarianism and voting fraud against the party and the results of the 1948 election in which the republican-dominated Congress overturned the elections because its candidate Calderón apparently lost because of the 1948 Civil War.

While the party was initially associated with coffee growing oligarchs and liberal elites and supported policies favorable towards these groups, the party moved towards Catholic socialist principles and alliance with the communists in the 1940s.