Shifts in Political Discourse and Moderation on Reddit During the 2016 and 2020 U.S. Presidential Elections

This paper compares online discourse in the Reddit Politosphere during the 2016 and 2020 U.S. presidential campaigns. In 2016, discourse focused on candidate personalities; by 2020, it shifted toward socio-political topics such as Trump’s presidency, the economy, early voting, and COVID-19. We also analyze the impact of the r/The_Donald ban, examining changes in sentiment, dominant topics, and news sources shared in liberal and conservative subreddits. Despite partisan differences, the top ten topics remained consistent across election cycles, though differently ranked. The results highlight that U.S. presidential elections are shaped by both candidates and issues, with their relative importance varying by election cycle.