At the annual meeting of the American Political Science Association, David A. Hopkins has a paper "The Suburbanization of the Democratic Party, 1992–2018." The abstract:
The outcome of the 2018 midterm elections has often been described as a “revolt of the suburbs,” in which white-collar professionals and other highly-educated middle-class voters residing in suburban areas expressed their dissatisfaction with the first two years of the Trump presidency by voting out many of the president’s fellow Republicans in significant numbers. A number of suburban House districts that previously leaned Republican flipped to the Democrats, including multiple seats in New Jersey, Pennsylvania, Virginia, Texas, and California—in fact, the former Republican stronghold of Orange County is now solely represented by Democrats in Congress.
The socially divisive Trump presidency and the alienation that it has provoked among college-educated suburban voters, especially women, has received considerable notice. Much less attention, however, has focused on the fact that suburban voters—once mostly, and even stereotypically, Republican—have been moving away from the party for a much longer time. As this paper makes clear, the much-celebrated electoral shifts of 2018 (and 2016 before it) merely further a much larger set of trends that long predate the Trump candidacy. Especially in the nation’s most populous metropolitan areas, Democratic presidential and congressional candidates have been gaining electoral ground since the 1990s.
While they were once arguably the more over-studied of the two parties, Democrats have received rather less attention from scholars and media analysts alike over the post-1992 period than they deserve—and certainly much less than the well-chronicled Republicans. The focus of this paper, part of a larger research project on the coalitional and ideological changes in the two major parties over the past three decades, is on the ways in which the suburbanization of the Democratic Party has influenced its internal composition and issue agenda. This suburbanization is the product of Democrats’ increasing electoral success in the suburbs, combined with the party’s declining popularity in rural areas and the relative population growth of suburban communities at the expense of large cities and small towns alike.
The central finding of the paper is that suburbanization has allowed Democratic candidates to move to the ideological left on cultural issues such as abortion, gay rights, gun control, and racial/gender matters. Public opinion data demonstrate that suburban voters are aligned with, or at least tolerant of, mainstream liberal positions on these issues. However, the presence of powerful suburban constituencies has proven much more limiting to a leftward partisan drift on taxes and economic redistribution, on which suburban attitudes are less consistently supportive. While Bill Clinton’s 1990s-era New Democratic approach attempted to win suburban votes by pulling his party toward the ideological center on both economic and cultural issues, subsequent party leaders (including Hillary Clinton herself) have reversed course much more aggressively on the cultural dimension than the economic dimension.
Finally, the growing centralization of the Democratic electoral, financial, and activist base in the suburbs of large metropolitan areas has implications for the operation of the congressional wing of the party. The decline of the party’s strength in rural areas has reduced the proportion of Democratic incumbents who had strong persona incentives to visible differentiate themselves from the bulk of the national party. At the same time, the majority of suburban representatives continue to be wary of openly aligning themselves with an ideologically purist approach to politics. the suburbanization of the Democratic Party, therefore, has led to a muting of internal differences. A suburban party, as it turns out, is largely a united party.