The Framers failed to anticipate universal suffrage and the American two-party system, let alone how these developments would change their system. Instead of letting Congress debate and decide policy, voters can now decide many issues directly. The chapter describes Americans grudging recognition that partisanship can lead to stable, responsible government. It then describes how 20th Century scholars developed rational voter models to formalize these ideas. It also asks how social voting, party leadership, identity politics, candidate charisma, and deep-pocketed donors change these results. Finally, it also argues that the existence of legislative deadlock lets comparatively small minorities take centrist compromises off the table. This forces the party system into presenting extreme choices that most voters oppose. The ensuing standoffs can last for years years and sometimes decades.