sentences:  During his vice presidency, Chang came into conflict with Lee Ki-poong, an influential Liberal Party member, who sent spies and placed him under surveillance.In 1959, he was appointed as a member of the Supreme Council of the Democratic Party of the Republic of Korea.In the same year, he became the Democratic Party's candidate for the vice-presidency and the running mate of presidential candidate Cho Byong-ok. Chang had attempted to become a candidate for the presidency, but once again he lost by a narrow margin, this time to Cho.