This document analyzes survey data from over 40 developing countries to understand determinants of radicalism, support for violence, and participation in anti-regime actions. It finds that individuals who feel politically and economically marginalized are more likely to harbor extremist views but less likely to join collective political movements. This potentially explains why marginalized groups are difficult to mobilize in nation-wide movements, despite their attitudes. It also finds that arenas for active political participation are more likely dominated by upper-middle income groups committed to preserving the status quo. Suppressing these forms of participation may push these groups towards more radical preferences. The findings suggest the poor may be caught in a cycle of increasing self-exclusion and marginalization.