Book excerpt: An incisive study that shows how Republicans transformed the US House of Representatives into a consistent GOP stronghold—with or without a majority. Long-term Democratic dominance in the US House of Representatives gave way to a Republican electoral advantage and frequently held majority following the GOP takeover in 1994. Republicans haven’t always held the majority in recent decades, but nationalization, partisan realignment, and the gerrymandering of House seats have contributed to a political climate in which they've had an edge more often than not for nearly thirty years. The Long Red Thread examines each House election cycle from 1964 to 2020, surveying academic and journalistic literature to identify key trends and takeaways from more than a half-century of US House election results in order to predict what Americans can expect to see in the future.