Here at Daily Kos Elections, we’ve watched special elections come and go for years, and we’d gotten accustomed to what used to be a normal occurrence: Democrats flailing in special elections.
Not this year.
Democrats are, on average, overperforming Clinton, overperforming Obama, and overperforming Democrats who ran for the same seats in prior years. And, they’re flipping Republican-held seats—eight of them so far!
Out of all the special elections with typical Democrat vs. Republican dynamics, Democrats have overperformed the 2016 presidential margin by more than 10 points in 25 of them. Republicans have overperformed by more than 10 points in just four—but one of those was actually a Democratic flip! On average, Democrats are doing about 13 points better than Hillary Clinton. The chart above shows the over- or underperformance of each race compared to Clinton’s margin.
Another way to look at it is that Democrats are playing on Republican turf, holding Republicans to within single-digit margins—or even flipping them!—deep within Trump territory. Above, only seats that were held by Republicans are shown. On the left, the 2016 presidential margin: a sea of red except for yesterday’s Florida districts. On average, Trump won these seats by 19 points. All but a handful might have been thought to be safe. On the right, the special election margin is shown; Republicans won these seats by an average of just 6 points, and, again, lost eight of them. Notably, Democrats have been able to keep Republicans to single digits even in the most Trump-friendly districts.
But 2016 was an unusual election, to say the least. What about comparing to 2012?
Democrats are, for the most part, doing better than President Obama did in 2012 as well. Democrats outperformed Obama by more than 10 points in 18 races, and Republicans outperformed by more than 10 in just three races. Democrats have outperformed Obama by about 10 points on average in 2017 special elections.
So Democrats are doing better than both Clinton and Obama, on average. It’s not just because 2016 was a weird presidential election that we’re seeing Democratic overperformance.
Let’s take a look at how this year’s overperformance compares to prior years:
This is all the data for the years 2013-2017, compressed into one graphic for direct comparison. Points above the diagonal line show Democratic overperformance, and points below the line show Democrats underperforming. In 2017, almost all the points are at or above the diagonal line. In the years 2013-2016, most of the points are below the line. On average, Democrats have been doing 17 points better in special election in 2017 compared to the years 2013-2016.
The graph above is a bit messy though. Let’s look at the data year by year:
The simplest interpretation is that the bulk of 2017 races (shown within the box) show Democratic overperformance (blue). In prior years, the bulk of the races show Democratic underperformance (red).
This graphic shows the distribution of special election over- and underperformances in each of the past five years, compared to the 2012 presidential results. In each year, half of the races fall within the range of the blue and red box. Another 15 percent fall along the blue line extending above the box, and 15 percent fall along the red line below the box. The best overperformers, 10 percent, fall above the tip of the blue line and are not shown; likewise, the worst underperformers are below the tip of the red line.
We can see that although there is overlap between 2017 and recent years in the extremes, there is a difference in distribution. The 25th percentile for 2017 elections, for instance, is higher than the average for the four prior years shown. We also see that although the bulk of the 2015 and 2016 special elections saw democrats underperforming, there are quite a few exceptions, with 2016’s 90th percentile reaching almost as high as 2017’s 90th percentile.
The 2017 numbers are, without a doubt, good news for Democrats. But what about earlier years? How does this compare to the last great years for Democrats, 2006 and 2008? Also, last night in Florida’s Senate District 40, the Democrat did worse than Clinton and worse than Obama, yet still managed to win and flip control of the district by doing 14 points better than the Democrat who ran there in 2016. Shouldn’t we account for that?
Stay tuned. We’ll get to all that next time.