Opinion Briefing Vol. 19-3: Voter Turnout Differences Do Not Change Support Distribution

Issue Briefing Vol. 19: D-7, Final Comprehensive Check of the Presidential Election Landscape

[1] Tracking Changes in Lee Myung-bak's Support Base: Hardcore Supporters + Bandwagon Effect - Kang Won-taek

[2] Remaining Points to Watch in the Presidential Election: Who Will Take Second Place? - Lee Na-young

[3] Voter Turnout Differences Do Not Change Support Distribution - Hyun Woo Lee

[4] Political Alliances 'Ineffective', Pro-Government Camp's Morality Offensive 'Ineffective' - Kwon Hyuk-yong

[5] The 17th Presidential Election is an Economic Election! - Jeong Han-wool

3. Voter Turnout Differences Do Not Change Support Distribution

Hyun Woo Lee (Professor of Political Science and International Relations, Sogang University)

Since democratization, presidential election voter turnout has decreased with each election, starting from 89.2% in 1987, reaching 70.8% in the 16th presidential election. Current projections indicate an even lower turnout for this election. How does changing voter turnout affect each candidate? In the past, when there was mobilized voting, it was conventional wisdom that higher turnout favored the opposition party, and lower turnout favored the ruling party. Since mobilization by the government was constant, higher turnout implied more voluntary voting, and these voters tended to support the opposition party.



In terms of age groups, the turnout among younger demographics has consistently been lower than that of older demographics. If voter turnout decreases, the turnout among younger demographics will decrease more significantly. Therefore, by examining which candidate is more supported by younger demographics, we can anticipate the advantages or disadvantages for each candidate. In the current survey, among respondents who answered 'I will definitely vote,' the difference between the 20s and 30s and those aged 50 and above is approximately 30 percentage points and 23 percentage points, respectively.



Regarding voting propensity, support for candidate Lee Myung-bak is about 5 percentage points lower than the average among 20s and about 10 percentage points lower among 30s. Candidate Jeong Dong-young shows higher support among 30s at 20.5% compared to other age groups. Meanwhile, candidate Lee Hoi-chang shows almost no difference in support across age groups.



Questions about voting intention are normative, so survey results are always higher than actual voter turnout. If we project the voting results based solely on those who are certain to vote in this survey, candidate Lee Myung-bak appears to be the most advantageous, as shown in [Figure]. This candidate shows a support rate of 51.5% among those certain to vote, which is 4.9 percentage points higher than their overall support rate. Candidate Jeong gains only an additional 0.4 percentage points in support among those certain to vote, showing no significant difference. For candidate Lee Hoi-chang, there is also almost no difference.



Ultimately, differences in voter turnout do not significantly alter the current support landscape. A lower turnout may further benefit candidate Lee Myung-bak, who is currently leading, while even a higher turnout would not distinctly favor either candidate Jeong Dong-young or Lee Hoi-chang, who are competing for second place.



□ A 50% vote share signifies strengthened legitimacy; 15% must be secured



If candidate Lee Myung-bak secures over 50% of the vote in this election, he will be the first candidate to achieve an absolute majority since democratization. In the 13th presidential election, candidate Roh Tae-woo won with 36.6% of the vote, becoming a minority president and exhibiting governance vulnerabilities from the outset of his term.



In fact, many democratic countries adopt the majority vote system, where a candidate must secure over 50% of the votes, rather than the plurality system, where the candidate with the most votes wins. Securing a majority vote signifies that a candidate can win regardless of the voting system, thereby strongly affirming the legitimacy of the administration and laying the foundation for strong leadership in the early stages of the term. Furthermore, it provides a favorable basis for the ruling party to appeal for stability in the upcoming general election.



Meanwhile, candidates Jeong Dong-young and Lee Hoi-chang each need to secure at least 15% of the vote. This is the threshold for recouping election expenses. Considering future political influence, it is burdensome for a candidate who has not reached the level of support deemed competitive by the state to claim to be a political leader.

[Figure] Comparison of Overall Candidate Support Rates and Candidate Support Rates Among Those Certain to Vote