You've probably heard that one thing that is bound to doom Democrats this November is the "enthusiasm gap," the fact that polls show Republicans far more enthusiastic about voting than Democrats. As Nate Silver tells us, this is really a turnout gap, and it's more about Republicans than Democrats. The Democratic base isn't actually particularly "dispirited," as we've heard -- they seem ready to turn out at something like historically consistent levels. What is likely to make the difference is that Republicans are really, really ready to turn out. This is basically what happened in 1994 -- reasonable Democratic turnout combined with extremely high Republican turnout.
But here's another way to think about it. When we look back over recent off-year elections, it seems like the thing that matters most in creating this dynamic is this question: Just how much do members of the out-party hate the president?
In 1994, Republicans really hated Bill Clinton, for instance, just as they hate Barack Obama now. Democrats didn't really hate George W. Bush in 2002, but they did really hate him in 2006. The number of seats the opposition picked up in each of these elections seems to follow pretty closely. The fact is that few things get you to the polls quicker than being mad. And if the feeling among members of the president's party is "Meh," then that will make things worse. Now let's try it with some actual data.
I used the last pre-election Gallup presidential approval rating for the off-year elections from 1982 to 2006, and created a figure I'm calling "out-party advantage." It's a simple number that captures how far presidential approval among each party is from the extreme. My assumption is that if the out party's approval of the president is zero, they're going to be highly motivated to turn out and vote against his party; similarly, if the in-party's approval of the president is 100, they're motivated to turn out. So the relative distance of those numbers from the top and bottom will give you a picture of the difference in their enthusiasm. For instance, the last Gallup poll showed Republican approval of Obama at 14 percent (14 points from zero), and Democratic approval at 81 percent (19 points from 100). Subtract 14 from 19 and you get an out-party advantage of 5.
There has been a fair bit of variation in this figure. For instance, in 2002, with memories of 9/11 still fresh, George W. Bush's approval just before the midterm election was 91 percent among Republicans and 63 percent among Democrats, giving the out-party a disadvantage of 54 points. Unsurprisingly, that was one of only two elections during this period when the president's party won a net gain of seats. Let's look at the picture:
This isn't meant to be strictly predictive -- I wouldn't want to say that this analysis shows that the Democrats will lose X number of seats. We're dealing with a small number of cases, and there are a lot of variables that can potentially affect things. But according to the approval rating data, this year's election looks to be in the neighborhood of 1982 and 2006, when the president's party lost 26 and 30 seats, respectively. Just one more thing to confuse you as we move toward November.
-- Paul Waldman
