New data reveals nine distinct ideological factions within the House of Representatives (1995–2018).

Faction as Party Sub-Brand

* Ideological factions function like political sub-brands.

* They allow legislators to precisely identify their partisan type and access faction-specific donor resources.

Data & Methods

* Analyzed House members' voting records, committee assignments, and other institutional roles over 1995–2018.

* Used regression discontinuity and logistic regressions on quantitative data to measure the impact of faction membership.

Key Findings

* Joining a faction significantly shifts a member's political orientation.

* Factions effectively target niche donor markets, attracting specific types of financial support conditional on institutional strength.

This research demonstrates that American politics extends beyond binary party choices and shows how factions leverage donors as strategic tools within major parties.