The Influence of Regional Population Demographic Changes on the Composition of Voter Cohorts and Voting Behavior during the Democratic Consolidation Process

This research examines how the changing demographic characteristics of voters affect generational structure of voters group and voting behavior on the presidential vote in South Korea. To do this, this research investigates the results from presidential elections in 2007 and 2017 by using the election data from 1997 as our baseline year which is not only recognized as the second presidential election corresponding with a democratic procedure, but regarded as a beginning of democratic consolidation in South Korea. Particularly, this research focuses on investigating how generational shifts in the Seoul metropolitan area (SMA) where has experienced dramatic demographic changes in the process of democratization since 1990s affect voters decision by categorizing 66 local government entities within the SMA according to changes in population demographics as well as political ideology. The results indicate that voters age is significantly correlated with the vote decision by ideological orientations, but its influence dramatically decreased in recent elections. Furthermore, this research utilized cluster analysis and ArcGIS to examine the similarity of municipalities within the SMA by clustering voters demographics and election results (political orientations) based on the data from the 66 municipalities of the SMA. The cluster results indicate that these municipalities could be divided into six clusters by population aging and the level of conservatism of political orientation. It is interesting to note that certain phenomenon across cluster types appeared very similar, yet the cause of these phenomena was completely different.