Biden outperforms Trump in highly contentious first presidential debate, study finds

MU political communication experts share results from virtual debate-viewing study.

September 30, 2020           
Contact: Eric Stann, 573-882-3346,  

this is a picture of Ben R. Warner

Ben R. Warner

Results of a virtual debate-viewing study among college students revealed that Joe Biden outperformed President Donald Trump in their first presidential debate.

The study, coordinated by the Political Communication Institute at the University of Missouri, included a survey of approximately 200 college students from Mizzou and Johnson County Community College in Overland Park, Kansas. Among the participants, 42% self-identified as Democrats, 39% as Republicans, and 20% as independents. Sixty percent were female and 40% were male.

The most notable findings from the survey relate to how the participants, from a partisan standpoint, viewed the nominees.

“Biden’s increase in favorability following the debate primarily came from partisan Democrats as well as partisan Republicans, representing a 10-point bump and an 11-point bump respectively,” said Ben Warner, associate professor of communication and co-director of the Political Communication Institute. “Biden’s favorability among independents changed very little. Trump, on the other hand, lost favorability among all partisan groups, especially independents, by six points.”

Other results from the survey showed:

  • Among the college students surveyed, 64% saw Biden as last night’s debate winner, with only 36% viewing Trump as the winner. This represents apparent favorability for Biden over Trump among participants.
  • Biden's performance in the first debate increased the students’ likelihood of voting for him from 50% before the debate to 55% afterward.
  • Support for Trump remained relatively the same throughout the debate, staying at approximately 37%.
  • Before the debate, 13% of students surveyed were undecided or did not plan to vote. Afterward, only 8% remained undecided or did not plan to vote.
picture of Mitchell S. McKinney

Mitchell S. McKinney

The debate viewers’ overall evaluations of Biden rose nine points, while evaluations of Trump decreased slightly by two points following the debate. Viewers were asked to rate both candidates on a “feeling thermometer” scale from 0-100. The average evaluation of Biden rose from 42 points before the debate to 50 points afterward, while evaluations of Trump declined from 36 points before the debate to 34 points afterward.

“Significantly, in the five previous election cycles, changes in candidate evaluations after the first debate ranged from zero to 10 points, with the highest changes being a 10-point increase for Hillary Clinton in 2016 and a 5.5-point increase for Mitt Romney in 2012,” Warner said. “This first debate between Trump and Biden is similar to the Clinton-Trump debates in that neither candidate was particularly well-liked going into the debate. As in 2016, Trump, who started at a worse position than Biden, lost even more ground among prospective voters at the debate’s end.”

The participants evaluations of moderator Chris Wallace in relation to those of Trump and Biden also fascinated the researchers. Fifty percent of those surveyed believed that Wallace outperformed both nominees during the night, as most participants saw Biden’s performance as adequate and Trump’s performance as generally bad.

Mitchell S. McKinney, professor of communication and director of the Political Communication Institute, observed how Trump’s constant interruptions agitated Biden as well as annoyed debate moderator Chris Wallace, who at times seemed unable to rein in Trump. Noting the unprecedented, chaotic nature of last night’s debate, McKinney expressed serious concern and hopes that future presidential debates will avoid the level of incivility and nastiness that the American public witnessed in this debate.

“Perhaps the biggest loser tonight is the American voter, who experienced little more than bickering and interruptions for 90 minutes,” McKinney said. “The overall image projected tonight by Donald Trump was one of a petulant president. Joe Biden avoided any major gaffe or stumble last night that would feed into the Trump narrative that Biden is too old or not fit to serve as president. In several of Biden’s responses, he spoke directly to the American public, expressing concern for their struggles.”

The research consortium led by the Political Communication Institute plans to conduct similar debate-viewing studies of college students for the two remaining presidential debates and the vice-presidential debate.

Editor’s Note: Media inquiries about this study can directed to Dr. Warner. To arrange an interview with him, please contact Eric Stann at 573-882-3346 or

The previous research cited here is available in the following sources:

McKinney and Warner (2013), “Do presidential debates matter? Examining a decade of campaign debate effects”:

Warner et al. (2020), “Reconsidering partisanship as a constraint on the persuasive effects of debates”:

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