Skip to main content
ABC News
The December Democratic Debate in 6 Charts

This holiday season, the Democratic National Committee gave the gift of one last primary debate in 2019. The stage featured just seven candidates, and despite a sleepy first hour, there was a lot of tension in the two-and-a-half-hour affair. Mayor of South Bend, Indiana, Pete Buttigieg came under fire from the rest of the field, fielding attacks from Sens. Amy Klobuchar and Elizabeth Warren in particular. According to the FiveThirtyEight/Ipsos poll, which used Ipsos’s KnowledgePanel to interview the same respondents before and after the debate, Klobuchar had a good night, attracting the most new potential support. Former Vice President Joe Biden also did well, earning the highest debate performance score from the viewers in our survey.

Maybe you were out holiday shopping — or watching the new Star Wars movie! — and missed it (hey, we don’t blame you), or you just want to know more about how the December debate may affect the race as we move into 2020. Either way, here’s the Democratic debate, summed up in 6 charts:

Which candidates performed best?

To kick us off, which candidates did viewers think had a strong performance? A weak one? To answer this, we compared each candidate’s pre-debate favorability rating1 to viewers’ ratings of his or her debate performance to see how candidates performed. This time, Biden walked away with the highest marks from respondents in our poll. But if it’s hard to see a decisive winner from last night, that’s because Biden, Warren and Sanders all performed roughly as well as we would expect given their pre-debate favorability. Buttigieg and Steyer received the worst marks for their performances, relative to their pre-debate favorability ratings.

How did voters’ priorities affect their views of the candidates?

According to our Ipsos survey, nearly two-thirds of likely Democratic primary voters prefer a candidate who has a good chance of beating President Trump over someone who shares similar stances with them on the issues. How these types of voters evaluate the candidates and their performances can vary, though, even if the differences are relatively small.

Voters who prioritize beating Trump thought Biden had the best debate performance, with Warren, Sanders, Klobuchar and Buttigieg tied with the second-highest marks. Among voters who prioritized issue stances, Sanders and Yang fared best.

Among voters who prioritize beating Trump, Biden did best

How well debate-watchers thought candidates performed in the sixth Democratic debate, by which type of candidate they prefer

Type of candidate preferred
candidate Similar issue positions Able to beat trump
Biden 2.8 3.3
Warren 2.9 3.1
Sanders 3.1 3.1
Klobuchar 2.7 3.1
Buttigieg 2.5 3.1
Yang 3.0 3.0
Steyer 2.5 2.8

From a survey of 3,543 likely Democratic primary voters who were surveyed between Dec. 13 and Dec. 18. The same people were surveyed again from Dec. 19 to Dec. 20; 720 responded to the second wave and said they watched the debate. The average ratings are out of 4 points, where 4 is best and 1 is worst.

Source: Ipsos/FiveThirtyEight

Who left a good impression?

We also wanted to see if any of the candidates managed to leave a good impression, as captured by their net favorability rating (favorable rating minus unfavorable rating) before and after the debate. By this metric, Yang and Klobuchar saw the largest gains, roughly six points each. But even with these increases, their net favorability scores are still lower than much of the rest of the field — better-known candidates like Biden, Sanders and Warren are viewed more favorably.

Yang and Klobuchar made positive impressions

Change in net favorability for candidates in a FiveThirtyEight/Ipsos poll taken before and after the December Democratic primary debate

Net favorability
candidate before debate after debate change
Yang +16.1 +22.4 +6.3
Klobuchar +11.0 +17.1 +6.1
Steyer +4.3 +7.3 +3.1
Warren +40.0 +43.0 +2.9
Sanders +40.5 +42.6 +2.1
Biden +43.2 +45.1 +1.9
Buttigieg +29.4 +27.5 -1.9

From a survey of 3,543 likely Democratic primary voters who were surveyed between Dec. 13 and Dec. 18. The same people were surveyed again from Dec. 19 to Dec. 20; 1,908 responded to the second wave.

Who spoke the most?

Klobuchar stole the mic Thursday, speaking the most words of any candidate. This was the first time the Minnesota senator earned this distinction, significantly improving upon her position in the last debate, where she came in fifth for words spoken. Buttigieg wasn’t too far off from Klobuchar, though, speaking just 200 fewer words.

Who held the floor?

Number of words candidates spoke in the sixth Democratic debate

Candidate Words Spoken
Amy Klobuchar 3,557
Pete Buttigieg 3,327
Elizabeth Warren 3,087
Bernie Sanders 2,891
Joe Biden 2,869
Tom Steyer 1,937
Andrew Yang 1,729

Source: Debate Transcript via ABC News

The fact that Klobuchar and Buttigieg spoke the most last night may be surprising given that they are significantly behind Biden, Sanders and Warren in the national polls. Normally, higher-polling candidates tend to get more air time, but in Thursday’s debate, the relationship between a candidate’s polling average2 and the amount of words he or she spoke was not particularly strong.3 For instance, while Sanders spoke about as much as his polling average would suggest, Biden spoke far less than expected.

Who mentioned Trump the most?

The candidates may not have spoken for equal amounts of time, but one thing they did have in common was name-dropping Trump. Klobuchar, for example, talked about Trump way more than Warren, who only mentioned him once. (This doesn’t seem to be a new strategy for Warren: She came in second to last in Trump mentions at the November debate, too, saying his name just twice.)

Who talked about Trump?

How often Trump’s name was mentioned by candidates in the sixth Democratic debate

Candidate Trump Mentions
Amy Klobuchar 11
Bernie Sanders 8
Joe Biden 6
Pete Buttigieg 6
Tom Steyer 4
Andrew Yang 4
Elizabeth Warren 1

Source: Debate Transcript via ABC News

On average, each candidate said Trump’s name about six times. But of course, this doesn’t cover every reference to Trump, as some didn’t call out the president by name — like when Sanders said “we have a president who is a pathological liar.”

Do you want even more debate coverage?

Cool graphics from other sites:

  • Going into the debate, The New York Times had a cool primer, which included tidbits like which candidates they expected to attack each other. It’s fun to look back now and see whether they were correct; notably, their speculation that Buttigieg might come under fire proved prescient, particularly in the back and forths with Warren and Klobuchar.
  • And if you want to see exactly how many times the candidates attacked one another, NBC News tracked it! Buttigieg came under fire the most, while Sanders dished it out more than any other candidate.
  • The New York Times also tracked how long each candidate spoke on each issue. Sanders spoke the most about health care, while Klobuchar dominated the conversation on electability. And foreign policy was the longest-discussed topic of the evening, racking up 15 minutes total.

And here’s more great post-debate analysis:

But really, all you need is … our debate coverage:


  1. Pre-debate favorability was calculated by assigning a 0 to 100 score to each respondent’s answer to the favorability question, where “very favorable” is equal to 100, “somewhat favorable” is equal to 75, “heard of, no opinion” is equal to 50, “somewhat unfavorable” is equal to 25 and “very unfavorable” is equal to zero. Scores were then averaged to create an overall favorability index for each candidate. Respondents who hadn’t heard of the candidate were not included.

  2. We are using FiveThirtyEight’s national polling averages.

  3. The correlation was 0.3, compared to 0.6 last time.

Maddie Sach was a politics intern at FiveThirtyEight.

Laura Bronner is a senior applied scientist at ETH Zürich and FiveThirtyEight’s former quantitative editor.

Yutong Yuan was an associate visual journalist at FiveThirtyEight.