The Decline of Split-Ticket Voting in U.S. Elections Between 1980 and 2020, the percentage of Americans voting for different parties across federal offices dropped from 26% to under 5%. This metric—split-ticket voting—historically served as a brake on partisan polarization and legislative gridlock. The collapse reflects increasingly straight-party voting patterns driven by cable media sorting, social media algorithmic reinforcement, and geographic self-sorting by ideology. The shift matters because it eliminates the moderating cross-party accountability mechanism; representatives no longer fear voters splitting their ballot, eliminating incentives for compromise and making primary elections (which favor ideological extremes) more consequential than general elections for determining actual policy outcomes.