Democratic Debate: Who Won and What Do Voters Care About?

The crowded June 2019 Democratic presidential primary debate

The Problem

The Democratic candidate who convinces voters she or he should run against President Trump in 2020 will have to determine how to connect to voters. Our analysis of the 2016 presidential debates revealed that Donald Trump was the most immersive Republican candidate and that Hillary Clinton failed to connect to voters, having very low immersion during her debates with Bernie Sanders.

This election cycle we collected real-time neurologic data from Democratic voters during the Democratic presidential debates on June 26-27 2019. Measuring neurologic responses showed what issues voters most cared about most, which candidates were most immersive, and what topics each candidate should focus on to build support with voters. Instead of simply asking people what they “like,” we measured Immersion, an objective neurologic measure of what voters care about.


The Study

We measured neural activity of Democratic voters (63% male, 38% female) who were mostly upper/middle class boomers while they watched the two nights of debates. June 26 data were collected in New York City and June 27 data were collected in Philadelphia.  Most of the voters were undecided regarding their preferred candidate.


We focused on the neurologic responses to candidates who led in polling among the 20 candidates debating. The data show that Senator Kamala Harris was the most immersive to viewers. Among the topics she discussed, immigration produced the highest immersion. Aligned with these data, Harris had the largest gain in supporters in post-debate polls. Mayor Pete Buttigieg and former Senator Bernie Sanders held their own against Harris, while Senator Elizabeth Warren was the least immersive of the major candidates. The table shows how the top candidates’ immersion compared to Senator Harris’ performance.

We also examined which issues generated the most and least immersion for all candidates. The most immersive topics were:

  1. Personal Information. Democratic voters were most immersed in the closing statements. Viewers wanted to know personal details about candidates.
  2. Social Issues. Democratic voter’s brains responded strongly to social issues, including abortion and race relations.
  3. The Economy. Even in a strong economy, Democratic voters were immersed in discussions about economic issues.
  4. Climate. Kamala Harris’ discussion of climate change as a crisis generated strong immersion in Democratic voters. Other candidates, including lesser known ones, also produced high immersion when speaking about the environment.
  5. Honorable mention: Immigration.  Although immigration produced only moderate immersion across all candidates, it generated peak immersion moments for the leading candidates and should continue to produce immersion in upcoming debates.

The least Immersive moments were:

  1. Corporations. Although Sanders and Warren continue to rail against big corporations, Democratic voters’ brains did not find this topic immersive. It should be shelved, at least for now.
  2. International Relations. Aggression from China and nuclear threats did not produce immersion in Democratic voters. Candidates like Tulsi Gabbard who focused on these issues failed to make an impact on voters.
  3. Healthcare. The data show significant neurologic frustration when healthcare was discussed indicating that candidates did not offer viable solutions.
  4. Guns. This traditional hot-button issue failed to immerse voters enough to make it to an important topic in future debates.

Key Take-Aways:

1. Although polls show Joe Biden leading, immersion data reveal that Kamala Harris is the one to watch.
2. Kamala Harris can pull away from the pack by discussing immigration and climate change. Joe Biden can fight back by focusing on the economy. Bernie Sanders should focus on the environment but then he fails to differentiate himself from Harris so his secondary focus should be on social issues.
3. Lesser known candidates did not immerse voters in the debates. These candidates should focus on making personal connections to voters and discussing social issues.

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