What do the numbers tell us about Independents? Though some scholars (Abramowitz among them) contend that there has been a marked rise in partisanship among the mass electorate in recent years and a solidification of partisan support, there is equally compelling evidence that the trek away from party allegiance that began in the 1960s continues through today.
According to data from the American National Election Study, in 1964 approximately 76 percent of the country identified as a “Partisan” (either weak or strong) in contrast only 24 percent identified as Independent or Leaning Independent (Leaners). By 1984 it was 65 percent to 35 percent and in 2008 it was 60 percent to 40 percent. Across that 42 year span the share identifying as Strong Partisans decreased from 38 percent in 1964 to 32 percent in 2008 and Weak Partisans declined from 38 percent to 28 percent. The share identifying as Leaning Independent, so-called Leaners, doubled from 15 percent to 29 percent. Though research has shown that many self identified Independents will express a partisan preference if pressed, there has been a clear trend toward an initial preference of Independent.
Through 1964 fewer than a quarter of the electorate self identified as a Pure Independent or an Independent leaning Democrats or Republicans. By 1968 that share had risen to 30 percent, and as of 2008 was at 39 percent of the electorate. There is no indication of decline in the Independent preference among voters. Though they may lean Democrat or Republican Americans are clearly less willing to express allegiance to one of the two major parties than they were in the 1950s and 1960s.
Some scholars use the same data to make the opposite argument concluding “if voters are becoming more partisan, we would expect declines in pure independents to result in increases in independent partisans. This is evident for both Democrats and Republicans.” That conclusion is debatable. If indeed we are seeing an increase in partisanship then perhaps we would see a decline in pure independents, but it is also likely that we would see a rise in partisans of all stripes – Strong, Weak and Independent. For Democrats, this has not happened and the rise in Independent Democrats appears not to have come from declines in pure Independents, but rather a decline in Weak Democrats – this does not suggest growing partisanship, but rather weakening partisanship.
The chart above tracks Democratic Party identification since 1952 and shows a clear decline in Democratic Party affiliation. From 1952 through 1968 Democratic Party affiliation averaged 54.9 percent of the electorate, from 1970 through 1980 the average was 52.3 percent and since 1982 the average is 49.8 percent. If one were to narrow the window to the 1990-2008 period the average is 49.7 percent. Though the share of Strong Democrats has rebounded from its lows in the 1970s it remains well below its average from 1952 through 1968. There also has been a marked decline in the share of Weak Democrats since the 1960s and it appears that the increase in Independent Democrats has been driven by the decline in Weak Democrats – not by a decline in Pure Independents. In short, fewer people are identifying as Democrats than did so prior to 1968 and those who do identify as Democrats are increasingly identifying as Independent Democrats.
The ANES data does show an increase in Republican partisanship, but this in entirely consistent with the collapse of the New Deal era and with it the dominance of the Democratic Party. Even among Republicans, however, there has been considerable growth among Independent partisans and evidence of a rebound among Strong Republicans following the lows of the 1970s – likely an artifact of the Nixon Administration and Watergate. The Republican share of the electorate averaged 33.9 percent from 1952 through 1968, then fell to 32.1 percent during the 1970s, and climbed to 38.2 percent in the decades since 1980. But the share of Strong Republicans from 1982 through 2008 was 12.2 percent, essentially the same as the average of 12.4 percent prior to 1968 – the “rise” in Strong Republicans is again likely an artifact of a collapse in Republican Party identification during the 1970s.
That said, the true growth area in partisan politics has been among the group of Americans Identifying as Independent, either Pure, or Leaning Democrat or Republican. Though there are fewer Pure Independents as a share of the electorate than during the decade immediately following the collapse of the New Deal Era in the late 1960s and during the height of the Watergate era there are more Pure Independents, Independent Democrats, and Independent Republicans today than during any measured era dating to the 1950s.
So when Gallup release a graph, like the one below, Democrats and Republicans should be concerned. Though Democratic Party affiliation matched a 20 year peak of 36 percent in 2008 it has since fallen to its lowest levels (according to Gallup) in 22 years. The Gallup data clearly shows that neither party can claim the allegiance of a majority of the electorate and since 1990 has rarely captured a plurality. At best, the data on party affiliation, whether from ANES or Gallup, suggest that there has been some solidification of the Strong Partisan base of each party, though collectively these Strong Partisans account for less than one-third of the electorate.
Are Independents independent in name only? No, not really. In The Myth of the Independent Voter, Keith et al., (1992) argued there has been little change in partisan attachment since the 1960s. Rather, the authors contend people identifying as Independents often reveal a preference for one of the two major parties when pressed to make a choice. These Leaners behave much the same as their more partisan counterparts with regard to issue positions and vote choice - this is the Abramowitx argument. In a 2009 article in Electoral Studies, political scientist John Petrocick argued, “Leaners are partisans. Characterizing them as independents underestimates the partisanship of Americans…”
But studies of partisanship often consider the views of Leaners at a given point in time or their votes in a specific election or examine the stability of partisan identification by merging all partisans – Strong, Weak, or Leaning – together and measure macro-level party identification. These measure do not take into consideration the temporal nature of partisan attachment and the propensity to change party affiliation over time. Additionally, in an era of candidate-centered politics it is possible that Idependents express a preference for the party of the candidate that they have chosen to support. So it would not be surprising that an Independent that leans Democratic votes the same as a Strong Partisan Democrat - in a specific election. But the Strong Partisan Democrat voted Democratic because of partisanship, the Independent, however, voted Democrat and expressed a Democratic preference because of the candidate.
But the lerger question really pertains to the size and stability of a governing coalition over time. For a President or a political party to succeed they must have a stable electoral coalition. If Independent voters are the fastest growing segment of the electorate and if they are truly independent, then Democrats and Republicans need to worry. But if folks like Alan Abramowitz are correct, then the parties can ignore the threat of the Independent voter.
A review of ANES data from a panel survey that included 2000, 2002, and 2004 however, shows that Independent Democrats and Independent Republicans (roughly a third of each party) are much less attached to their party than either Weak or Strong partisans over time.
Strong as well as Weak partisans left their respective parties at far smaller rates over time. Equally worthy of not, Independent Democrats and Republicans who left their 2000 party were just as likely to identify with the opposition party in 2002 and 2004 as they were to simply identify as pure Independents.
A review of 2004 partisan identification shows that fully one-third of Independent Democrats and Independent Republicans in 2004 identified with another party or no party in 2000. Simply stated, partisan identification is much less stable among Independent partisans and Eric McGhee and Daniel Krimm (in a 2009 issue of Polity) found that Independent partisans are more moderate than Strong partisans.
Abramowitz and others are correct - Independent Partisans do vote much like their Strong Partisan counterparts in a given election, but the ANES panel data suggests that a significant share of Independent Partisans (between a quarter and a third) may well have a different partisan stripe by the next election cycle. Far from the “unmoved mover” described in The American Voter (Campbell et al., 1960), partisanship among Independent Partisans moves and they are the fasted growing segment of the electorate.
Fully 11% of the electorate are Pure Independents, another 30% are Independent Partisans (about 18% Democrats and 12% Republicans) and between one-quarter and one-third of these Independent Partisans are far less attached to party from election to election. At the very least, this suggests a 20% voting bloc that is quite volatile - in a country where our presidential elections have been decided by margins of 7 percentage points or less since 2000 and the difference between the national two party vote share in House elections has averaged about 5 percentage points since 1990.
Independent voters are no myth, they matter, and (when you include among them Independent Partisans) they absolutely sway elections. Indeed, the present and highly competitive political era in which we are living is a direct result of a decrease in partisan attachment coupled with an increasing level of partisanship among each party's relatively equal (and small) in size base.