Original sentence: Calles could not succeed himself as president, so he created a political party, the Partido Nacional Revolucionario (PNR).During his term as president, he oversaw the passage of a new labor law and inaugurated the zoo in Chapultepec Park.He ran against José Vasconcelos, Obregón's Secretary of Public Education, noted for his stance against corruption and Calles's authoritarian rule.It was believed at the time that Vasconcelos actually won the election.Ortiz Rubio had no independent power base that could serve to counter balance to Calles and so as president he was seen an ineffective leader.President-elect Álvaro Obregón was assassinated in 1928, leaving a power vacuum
Edited sentence: Calles could not succeed himself as president and he took a brilliant step, creating a political party, the Partido Nacional Revolucionario (PNR).During his term as president, he had overseen the passage of a new labor law and inaugurated the zoo in Chapultepec Park.He ran against José Vasconcelos, Obregón's brilliant Secretary of Public Education and a national luminary who took a stand against corruption and Calles's authoritarian rule.Ortiz Rubio had no independent power base that could serve to counter balance to his powerful patron Calles and so as president he was seen an ineffective leader.President-elect Álvaro Obregón was assassinated in 1928 by a Catholic mystic, leaving a power vacuum.Some believed at the time that Vasconcelos actually won the election.Such a position meant that he had no independent political base