Overview
The Social Democratic Party (Spanish: Partido Social Demócrata, PSD) was a conservative, small and elitist, but influential Bolivian political party formed by middle-class intellectuals.
The Social Democratic Party was founded in 1944 by younger, conservative Bolivians committed to modernization and the technological and technocratic strategies they believed necessary to achieve it.
Led by Luis Adolfo Siles Salinas (Hernán Siles Zuazo's half-brother), Roberto Arce, Manfredo Kempf Mercado, Gastón Arduz Eguia, Alberto Crespo Gutiérrez, Tomás Guillermo Elio, and Mario Estenssoro, the party embraced developmentalist, nominally Christian-Democratic principles.
For the 1947 general elections, the Party allied with the Liberal Party and Revolutionary Left Party and backed Liberal Luis Femando Guachalla as the coalition's presidential candidate.
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