Demography

Party Affiliation over Time

It seems, especially in the midst of an election year that the political parties are long established and permanent. While we don’t have an especially high rate of turnover in major political parties we do have one.

The Republicans became the Democratic Republicans, which eventually become the Democrats (an extremely brief summary of a rather lengthy chunk of American History). The Republican party, as we know it today, actually came out of the Whig party (well, a splinter faction, sort of. No one said politics was straight forward).

At any rate, political parties are not constant and neither is their membership. Gallup has a nice collection of data on party affiliation that we referenced last week in things that make surveys hard. Since they’ve provided it as a table, here is the graph:

Party Affiliation over time; data from Gallup

Looking at Gallup’s data, we can make several observations. Since 2004, the general trend has been an increase in people identifying as Independents, and a decrease in both Republicans and Democrats. We also notice that declines in either major party tend to coincide with increases in Independents.

The top of the graph is 50%, and while none of our three categories make it that high, Independents come the closest (highest percent independents was 47%, which occurred both in October of 2013 and October of 2014).

A “Zoomed in” version of the previous graph, from 2012 on

Taking a closer look at things (note that I’ve changed the vertical scale as well, the bottom is now 15%) from 2012 on, we can see a large drop in both Republicans and Democrats in 2013 that has a corresponding rise in independents. 2018 had a decline in Independents that mirrors a rise in Democrats.

The difficulty with examining trends is “How far do we have to zoom out?” Over a large amount of time, it’s difficult to see the impacts of smaller events but easier to examine long term trends. Another consideration is that what looks like a clear trend on the small scale may not reflect the trend in the long term.

Political polling doesn’t give us all that much long term data. Do we have enough to make predictions from? Well, the people making predictions certainly seem to think so!