[4] However, following the success of the opposition New Korean Democratic Party (NKDP) in the National Assembly elections in April 1985, calls were made for constitutional changes.

[7] Nearly a month later on 10 June, mass protests broke out as Roh Tae-woo, the chair of the DJP, was announced as Chun's successor.

[3] In the following weeks, multiple protests were held, and on 29 June Roh capitulated to demands for constitutional amendments, proposing an eight-point plan.

At the convention, 7,378 delegates nominated former Commander of Capital Defense Roh Tae-woo, who was the only option on the ballot paper, for president.

[9] The Reunification Democratic Party (RDP) National Convention was held on 9 November at Sejong Center for Performing Arts in Seoul.

[10] The Peace Democratic Party (PDP) National Convention was held on 12 November at Sejong Center for Performing Arts in Seoul.

Kim, viewed as a more moderate, pragmatic politician and open to compromise, attracted the backing of senior retired military figures opposed to the incumbent government,[12] and South Korea's growing middle class who wanted an end to the military in politics, and in particular, urban white collar workers seeking stability to continue economic growth.

[12] In particular, Jeong Seung-hwa, the former army chief of staff falsely accused of plotting Park Chung-hee's assassination which Chun and Roh used to justify their power grab in 1979, came out to support Kim.

Despite attempts to moderate that image, he attracted most appeal among the dissident movement, such as human rights activists, students, organized labor, and lower-income voters.

[12] According to American Central Intelligence Agency (CIA) documents obtained by Hong Kong's South China Morning Post through a freedom of information request in July 2019, the military-backed ruling forces feared the loss of its hand-picked candidate Roh Tae-woo that it drew up detailed plans to fix the election result.

The brief added that the government was "considering black propaganda and dirty tricks, reportedly to include ballot tampering; some officials now appear prepared to go even further" and “ruling-camp planners have thought about fabricating evidence of ruling-party fraud to give Chun an opportunity to declare the election null and void if government projections from early returns indicate Roh is losing”.

[13] According to Lynn Turk, at the time a Seoul-based US State Department foreign service officer who watched the campaign and the election closely on a moment-to-moment basis noted the allegations as “a very interesting story”, but stated “the votes were counted fairly and Roh really did win fair and square.” He added: “On election night each of the four parties had observers at each polling place and got a carbon copy of the public hand-counted vote.