An assessment of a four-stage conceptual model reveals that critical thinking has indirect positive effects on political participation through its direct effects on personal control, political efficacy, and democratic attitudes. The model establishes causal relationships among selected personality variables (self-esteem, personal control, and political efficacy), critical thinking, democratic attitude, and political participation. A total of 118 undergraduate and graduate students were given a series of instruments to measure these variables. Data were analyzed using path analysis to determine direct and indirect relationships among the variables. Critical thinking positively affects personal control, political efficacy, and democratic attitude. Political efficacy and democratic attitude positively affect political participation. Personal control has a strong direct effect on political efficacy. Thus, critical thinking is significantly related to political participation. The implications are that the teaching of critical thinking should be a major focus of citizenship education. Copies of measurement instruments and statistical tables are included. (KC)