Human behavior is only partly based on reflective thinking whereas many, cognitive less sophisticated activities especially might be initiated in a habitual manner. Since “conventional political activities” require more effort than “unconventional” or electoral political participation which usually are less binding and event-related, the latter might be activated via an “affective” pathway represented by political interest (Hypothesis I). In contrast, conventional action probably requires a reflective behavioral system. Subjective political competence (i.e., internal political efficacy) is thus hypothesized to be a necessary precondition to initiate conventional participation (Hypothesis II), possibly supplemented by political interest. Both assumptions are followed using an online panel sample of Turkish migrants in Germany. In addition, the German National Educational Panel Study (student cohort) provides data for a comprehensive comparison and a validation of results. Qualitative interviews were also conducted to supplement with additional affective and reflective indications. Multiple regression analyses are used and complemented with more complex path models to examine both hypotheses. Regarding the Turkish migrants sample, results support Hypothesis I and point to an overwhelming importance of political interest in the prediction of legal political activity, i.e., voting and conventional as well as unconventional political action. Regarding conventional activity, however, analyses show partial evidence for Hypothesis II: both variables of cognitive politicization only have indirect effects being mediated via readiness to participate in conventional political action. Analyses of qualitative data support these findings, drawing attention to facets of differing types of political activities and linking them to a lack of trustworthiness, frustration, experienced disappointment, (lost) ideals, fun, thorough consideration. Further evidence suggests that collective identification and subjective maltreatment can be affective preconditions of both variables of interest. The findings are discussed with regard to a possible societal divide caused by missing acceptance perceived by migrants and the importance of sociopolitical and emotional integration of migrants in particular.