One of the driving forces of modern American politics has been the kaleidoscopic reshaping of the electorate, as minorities have steadily increased their share of the vote while whites—particularly those without advanced education—have declined. But these trends have affected the two parties in strikingly different ways, likely to further diverge in 2016.

As the first chart shows, the change in the overall electorate has been steady—and profound. Since Ronald Reagan’s landslide reelection in 1984, working-class whites—defined as those whites without a college degree—have plummeted from around three-fifths of all voters in presidential elections to just over one-third in 2012. The share of the vote cast by whites with a college degree increased from just over one-fourth in 1984 to slightly more than one-third in the 1992 election (Bill Clinton’s first victory) and has largely stabilized there since.
Filling the space left by the receding white working-class constituency, minority voters have consistently grown their share, from just 11 percent in 1984 to 28 percent in 2012. If the 2016 electorate follows these historic trends, minorities would likely rise to 30 or 31 percent of the vote, college-educated whites will remain about constant, and the white voters without college degrees would continue their decline by about another two percentage points.