Discerning the conditions that shape political trends is one of the more demanding challenges facing political commentators. It is also subjective. Analysts often see what they want to see in trends. To many analysts, demography is political destiny ( Scammon and Wattenberg 1970: 45). It is presumed that social and economic conditions shape, if not determine, political behavior. For example, people who live in suburbs tend to vote more Republican. Drawing on that relationship, the presumption is that the greater the proportion of people living in suburbs, the greater the support for Republicans. Minorities, on average, have a greater need for government and are more likely to be supportive of government action. So, the higher the percentage of minorities, the better Democrats will do. Although there are always exceptions, enough evidence exists of the connection between social and economic conditions and partisan political behavior to attribute them a significant impact.
Other analysts emphasize the powerful role of ideas and values in shaping political trends. They argue that differences in views about the proper role of government and assessments of its efficacy shape public support for government. Some argue that values and views of which social practices should be endorsed or condemned by government are more important as sources of political views and partisan support than self-interest. Reactions to abortion, crime, and civil rights, for example, are seen by many analysts as important and more divisive than class issues.
Not only do analysts differ about whether demographic or ideological factors are more important in shaping politics, they also differ about whether trends in these areas over the last several decades have created conditions favoring Republicans or Democrats. In general, there are two competing interpretations of how social change has shaped which party