Raphael Dominguez.
The Progressive Party is currently the only legal political party in the United States of Mexico. The Progressive Party was established in 1965 by President Vincent Mercator in preparation for the 1965 Mexican elections. It ran Raphael Dominguez for President in that election, as well as a full slate of candidates for the Assembly and Senate. In some cases, multiple candidates were allowed to run for an office, to give voters the illusion of democracy, but all were chosen by Mercator.
On election day, November 1965, out of 31 million votes cast, Dominguez received only 14.7 million. Some 9 million write-in votes were cast for the late Admiral Paul Suarez, who had won the last free election in 1950. Mercator was furious with the results, and he subsequently changed the election law to prevent a repetition in the future. He swore in Dominguez on 22 November, and took his previous office as Secretary of War, from which position he continued to rule the U.S.M. from behind the scenes.
In For All Nails, Dominguez's successor, Immanuel Moctezuma, forces Mercator to flee Mexico in December 1975.