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Midterm Balancing Still True?

Bob Erikson, Chris Wlezien and I have been working on a paper about midterm balancing. We see it as still very viable and find solid evidence that it happens. In what follows, I have copied in portions of the paper. They will reveal what we did, what we found and what it all means. The paper is under review at POQ.

In 1998, as the unpopular impeachment of President Bill Clinton was unfolding, Clinton’s Democrats gained seats in the House of Representatives. In 2002, in the shadow of 9/11, President George W. Bush’s Republicans gained House seats as well. These two recent instances might make it seem commonplace for the presidential party to gain House seats at midterm. Indeed, the early interpretations of 2002 by Jacobson (2003) and Campbell (2003) emphasized the theme that this election unfolded as normal politics. Jacobson even chose not to remark about the historical significance of the presidential party gaining seats. The historical pattern, of course, is that the presidential party loses seats at midterm. This in fact had been more than simply a pattern, and almost a deterministic law of politics. From 1842 through 1994, the presidential party gained seats (as a proportion of the total) only once—in 1934 as the FDR-led Democrats’ surged with a gain of nine seats. This was a spectacular run of 38 presidential party losses in 39 midterm elections. Clearly, forces are at work in American politics to diminish the electoral standing of the presidential party at midterm.

The two most common explanations for midterm loss come under the headings of “coattails” and “balancing.” The coattail explanation begins with the congressional vote in the presidential election year prior to the midterm election. It holds that the surge in support for the presidential winner (“coattails”) artificially inflates support for the presidential winner’s party in the presidential year (A. Campbell, 1966; Hinckley, 1967; J. Campbell, 1985; Campbell, 1991). The balancing explanation focuses on the congressional vote in the second of the two elections. It holds that the midterm electorate supports the out-party to push Congress in the opposite ideological direction of the president in order to achieve greater ideological balance in government (Erikson, 1988, 2002; Alesina and Rosenthal, 1995; Mebane, 2000; Mebane and Sekhon, 2002; see also Fiorina, 1996, regarding balancing more generally).
What do the violations of the midterm loss rule in 1998 and 2002 teach us about the competing theories of midterm loss? The coattail theory provides a handy excuse for the two exceptions. Since there evidently were no presidential coattails in either 1996 or 2000, there were no coattails to withdraw in 1998 or 2002. Balance theory, one could argue, was more discredited by the 1998 and 2002 exceptions (Campbell, 2003), particularly since moderate voters had every incentive to tack right in 1998 and left in 2002. Of course the theory could be salvaged by accounting for the effect of the Clinton impeachment in 1998 and 9/11 in 2002. While this type of post-hoc rationalization normally is to be discouraged, one could reasonably argue that these two events were abnormally large interventions that moved voters toward rather than away from the sitting president’s party at midterm.
In this paper, we offer a new test for ideological balancing as a source of midterm loss. For this test, we exploit survey researchers’ frequent monitoring of the “generic” congressional vote during midterm years. The generic poll question asks respondents which party they plan to vote for in the upcoming congressional election. These generic polls can provide crucial clues regarding the timing of the electorate’s shift from the presidential or “in” party to the “out” party. To begin with, consider respondents who are asked their congressional preferences early in the midterm year, at roughly the halfway mark of the election cycle. Unlikely to have given much if any advance thought to their vote for the House of Representatives at such an early date, they will offer poll responses that are too premature to incorporate beliefs about voting for the out-party as an ideological counterbalance to the president. Now, consider respondents asked for their generic vote on the eve of the election. By this point in time, their thoughts may have turned to the election and are likely to incorporate any cognitions they will make about the need for ideological balancing. Our analysis supports this hypothesis.

Recent midterm gains by the president’s party would seem to cast doubt on the notion that the electorate moves toward the out party in midterm elections as an ideological counterweight to the president. This paper provides new evidence in support of the balancing theory, by exploiting the predictive power of generic polls of congressional party preferences at midterm. At regular intervals throughout the midterm years from 1946 through 2002, pollsters have monitored congressional party preferences via their generic poll questions. Contrary to the frequent skepticism in the media, the generic polls are quite useful for forecasting midterm election outcomes, requiring only the proper discounting of the size of the partisan gap in the polls. As we have seen in this paper, the predictive power of generic polls is enhanced further by taking into account the party of the president. This provides the evidence for ideological balancing.
Our demonstration is simple. We regress the midterm vote on the generic polls plus a dummy variable for the presidential party. When the generic polls are measured early in the midterm year, the presidential party has a visible and highly significant negative “effect” on the vote. Over the course of the campaign, this effect declines toward zero. The only plausible interpretation is that (with 2002 a clear exception) the electorate becomes more sympathetic toward the out party as the campaign progresses. At the start of the midterm year, the electorate responds to the generic poll question with a party preference that does not take into account the party of the president. As the campaign progresses and voters focus more on the upcoming election, the electorate increasingly rejects the presidential party, a behavior that is not plausibly tied to presidential coattails two years before.
This growing attraction to the out-party, we contend, is due to the electorate increasingly focusing on the vote for Congress as a way of ideologically balancing the president. Some may deny the motivation that we attribute to the voters for their movement away from the presidential party during midterm campaigns. If the shift is not motivated by ideology and policy differences between the parties, of course, critics are invited to provide alternative explanations.
We close with a note of caution. We must be aware that the data provide a strong general rule but one that can have strong exceptions. Consider the generic polls of 2002. Plugging the generic polls from that campaign into the model, the Democrats “should” probably have controlled the House following the 2002 election instead of losing ground. But despite this sobering forecasting failure, the evidence is compelling–almost always, the out-party gains strength during the election year.

One Comment

  1. Joe,

    I'll have to digest this a bit. But my quick comment is: I hope you display your time-series results (during the election campaign and over the decades) using the secret weapon, not using those ugly regression tables.