Replication Data for: Rally ’round the mask: Congressional social media images and masking during COVID-19

During national crises, political elites often rally ’round the flag, promoting a central message to restore unity and calm the public. COVID-19 provided a crisis. But did elites rally? The pandemic occurred at a point of extreme polarization in the United States, which threatens the potential for a rally. In this note, we argue that messaging about masking during COVID-19 offers an opportunity to test the comparative effects of a rally versus polarization. To do so, we use a unique measure: visual public communication by Members of Congress (MOCs). We extract 340,000 images from Congressional Twitter and Facebook accounts and employ supervised machine learning methods to identify when MOCs post images of people wearing masks. We find more evidence of rally effects and polarization. Trump’s actions are especially important: while Trump-loyal Republicans are less likely to post masks, all Republicans increase posting masks after Trump first appears wearing a face mask.