過去探討投票決定的因素涵蓋社會學派、社會心理學派，以及理性抉擇學派所提出的理論，這三大學派解釋了許多國內中央層級選舉的投票行為，但地方選舉的研究卻相對地缺乏。地方縣市長選舉是否同樣受到這些因素的影響？何者影響較大？在不同的縣市是否呈現不同的解釋模式？本研究發現，在任何單一縣市中，社會學途徑的影響都最弱，社會心理學途徑的影響都最強。雖然如此，四縣市之間各途徑影響力仍有不同。將四縣市合併比較，台中市選民相較於高雄縣選民，展現更高理性抉擇的傾向；相對地，高雄縣選民相較於台中市選民，則更偏向候選人因素的心理取向。因此，台中市與高雄縣選民投票行為分別位於這兩種投票途徑的兩端，而台北縣、雲林縣的選民投票行為則介於理性選擇與社會心理學取向之間。

The factors affecting voting behavior have been discussed in sociological, social psychological, and rational choice theories. These three approaches explain many voting behavior cases in terms of central level national elections but pay relatively less attention to local level elections. Are the elections for county magistrates and city mayors affected by these three factors? Which of these three influence local elections more? Do the elections in different counties and cities reflect different explanation models? We find that in any of the four counties and cities, the sociological approach is weakest, while the social psychological is strongest, in explaining voting behavior. Nonetheless, the influence of these approaches differs among these four counties and cities. Comparing these four counties and cities, we find that the rational choice approach is more effective in Taichung City than in Kaohsiung County. Conversely, the voters in Kaohsiung County prefer the psychological approach of candidate’s factor more than the ones in Taichung City. Consequentially, on one hand, the voting behavior models of voters in Taichung City and Kaohsiung County are located in the extremes of the two voting approaches. On the other hand, the voting behavior models of Taipei County and Yunlin County are situated between the approaches of rational choice and social psychology.