With the GOP primary now all but officially over—congratulations, Mr. Romney—we can safely declare it swing voter season. As the general election campaign heats up, ever more attention is going to shift to that special class of voters who we presume will be responsible for picking our next President. But there’s good reason to believe that the vast majority of Americans, including professional journalists and campaign operatives, wouldn’t recognize a typical swing voter if they met one.
Indeed, the application of the term “swing voter” deserves a lot more scrutiny than it generally earns. As it is, the term is thrown around carelessly to apply to large demographically or ideologically defined groups. The most common assumption, for example, is that swing voters are synonymous with political independents, but as I explained at length in a recent book review, that is an utterly fanciful notion.
Instead, the simplest and clearest way to think about it is on the level of the individual voter. For an individual voter to qualify as a swing voter, the relevant criterion that needs to be fulfilled is persuadability. And that’s not a quality that’s exclusive only to those who are completely undecided, or who are only weakly committed to a candidate. Even those who are moderately committed can be persuaded to deepen their commitment. And the deepening of an existing affiliation with a candidate can be just as significant, both statistically and electorally speaking, as attracting mild commitment from someone who had previously been mildly committed to another candidate.
Persuadability, then, is not logically restricted to voters in the center; it can potentially be far more broadly distributed. That is what William Mayer found in his analysis of swing voters based on National Election Study data. Swing voters are least likely to be found among strong partisans (12 percent of this group); more likely to be found among independent leaners (27 percent) and weak partisans (28 percent); and most likely to be found among pure independents (40 percent). But since pure independents are such a small group, they wind up being just 13 percent of all swing voters, actually less than the number of strong partisans among swingers (18 percent). Another 28 percent of swing voters are independent leaners, and the largest group, 42 percent, are weak partisans. Thus the overwhelming majority (70 percent) of swing voters are weak or independent leaning partisans—the kind of voters whose probability of support for “their” candidate is more usefully thought of as being movable from 70 to 80 percent than from 45 to 55 percent.
Of course, even if swing voters are hard to pin down, that doesn’t mean campaigns shouldn’t try to reach them. They are by definition the most persuadable voters and, while estimates vary, in a typical campaign they might be around a fifth of voters. But given the fact that the overwhelming majority of swing voters are partisans, the logical place for a campaign to start is by consolidating support among “their” swing voters—that is, by driving up their support rates among weak partisans and independent leaners. As a bonus it would be useful if the campaign message reached toward the center and appealed to pure independents though numerically this is less important. The least promising group is clearly the partisan swingers of the other side. Whatever message might chip away at this group’s support for the opposing candidate seems unlikely to be the same message that would consolidate weak and independent leaning partisans behind a campaign’s candidate.
The same “one size does not fit all” applies to the demographics of swing voters. Since swing voters are everywhere, a campaign might be concerned with reaching swing voters among both Hispanics and the white working class. But it seems unlikely that the same message, especially of some ill-defined centrist variety, will appeal strongly to swingers in both groups. Boringly, it may come down to the mundane task of setting support rate targets among these and other demographics and figuring out how to hit each of the targets. But however boring it may seem, that’s how you win elections.