Who Won The South Carolina Democratic Debate?

To better understand which candidates did well or poorly, we plotted how favorably respondents rated the candidates before the debate vs. how debate-watchers rated candidates’ performances afterward. The first thing that stands out from last night’s debate is that Democratic voters were not especially thrilled with anyone’s performance. And as you’ll see, there’s no consistent theme to who voters responded well to, and their responses add up to a somewhat muddled picture of the debate’s effects. That said, Sen. Bernie Sanders and former South Bend, Indiana, Mayor Pete Buttigieg got the highest average performance marks, closely followed by former Vice President Joe Biden and Sen. Amy Klobuchar.

Sen. Elizabeth Warren, on the other hand, got a middle-of-the-pack performance score, but because of her relatively high pre-debate favorability ratings, you’d expect a lot of voters to be predisposed to viewing her debate performance in a positive light, and her score doesn’t look as impressive in comparison. (The same is true for Sanders, even though he got the highest average marks.)

The numbers behind the chart

In terms of raw debate grades — respondents graded candidates on a four-point scale (higher scores are better) — the clear losers were billionaire activist Tom Steyer and former New York Mayor Michael Bloomberg. However, their scores do look a little better judged against their relatively mediocre pre-debate favorability ratings.