Polarization, Demographic Change, and White Flight from the Democratic Party

Abstract

Whites have become less likely to support the Democratic Party. I show that this shift is being driven by two mechanisms. The first mechanism is the process of ideological sorting. The Democratic Party has lost support among conservative whites because the relationships between partisanship, voting behavior, and policy orientations have strengthened. The second mechanism relates to demographic changes. The growth of liberal minority populations has shifted the median position on economic issues to the left and away from the median white citizen’s position. The parties have responded to these changes by shifting their positions, and whites have become less likely to support the Democratic Party as a result. I test these explanations using 40 years of American National Election Study and DW-NOMINATE data. I find that whites have become 7.7 points more likely to vote for the Republican Party, and mean white partisanship has shifted .26 points in favor of the Republicans as a combined result of both mechanisms.