He won against the Liberal leader Fernando Guachalla and the reformist candidate Víctor Paz Estenssoro, who led the Movimiento Nacionalista Revolucionario (Nationalist Revolutionary Movement).

Rising expectations and demands from an increasingly activist and indeed, violent, popular class, combined with the unwillingness or inability of the governing elites to give concession that would undermine their power, led the country to the very brink of civil war.

When the legislative elections of 1949 confirmed the dramatic ascendancy of the parties of the Left, the PURS leadership lost trust in the relatively more conciliatory Hertzog's ability to control the situation.

Following the 1952 Bolivian National Revolution that brought Paz Estenssoro's MNR party to power, the ex-President remained exiled in the Spanish capital, later moving to Buenos Aires, where he died.

Hertzog again ran for President of Bolivia in 1966 on behalf of remnants of the pre-Revolution parties which had formed Democratic Institutionalist Alliance against René Barrientos, but only got a small share of the vote.