At TNR today, my TDS (The Democratic Strategist) colleague Ruy Teixeira offers a useful reminder going into the general election that the term “swing voter” is not synonymous with “independent” or even with “undecided” voters. They are essentially persuadable voters whose probability to support a given candidate can be affected by messaging, external events, or even get-out-the-vote efforts. And they are all over the partisan and ideological spectrum:
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.
The complicating variable, of course, involves the certain voters who move from one of two competing candidates to the other marginally reflect more “bang for the buck” than those whose decision wavers between voting and not voting at all, since persuading that particular swing voter adds one vote to column A while deducting one vote from column B. But in the end, a vote is a vote, and increasing the pool of voters by one often requires true persuasion. The most important thing to remember is that the tendency to think of the electorate as sharply divided between “base” and “swing” voters is often highly misleading. Aside from the certain voters whose preferences are unshakable, it’s all a matter of degree.