From an early, incorrect consensus that party identification was free of the short-term influences of political life, its aggregate, macropartisanship, drew little scholary notice. Though macropartisanship, typically seen as a biennial time series, appears essentially constant, our quarterly treatment demonstrates substantial and notably systematic movement of this crucial barometer of the U.S. party system. We demonstrate that it varies systematically with respect to time, has electoral consequences, and can be modeled as a function of economic evaluations and approval of the incumbent presidential administration. Macropartisanship, we argue, is a variable like others, subject to routine ebb and flow as citizens in the aggregate reflect their experiences of politics onto the parties. Its medium-term movements of considerable magnitude are lasting enough to matter but occur without connoting shifts in the underlying party system and can be understood without invoking the crises and convulsions of realignment theory.