As the demographics of the United States have changed since 1980, so have the coalitions that make up both the Republican and Democratic parties.
Introduction and summary
Demographics are not destiny, but steady and predictable changes to the electorate play an important role in defining the landscape of American politics. Most demographic groups have a political lean, so a group increasing or decreasing in size over time will tend to benefit one party or type of politics over another. The most well-known example is the growth of the nonwhite population in the United States, which—since nonwhites tend to lean heavily Democratic—is typically viewed as tilting the electoral terrain somewhat toward the Democrats over time as well as increasing the weight of nonwhite voters within the Democratic Party over time. But other changes are important, such as the decline of noncollege educated voters, particularly whites; the aging of the adult population; and the rise of new generations to replace older ones.
In this report, we will explore the effect of these changes on the demographic composition of the electorate and, especially, on the composition of the two major political parties. Reflecting the latter focus, this analysis will not focus on how many individuals from a given demographic group voted or will likely vote for the Democratic or Republican candidate in a particular election. Rather, it focuses on how many people who voted or are likely to vote for the Democratic or Republican candidate in a particular election belong to a given demographic group.