With nearly all political candidates, officeholders, and organizations using the platform, Twitter has become an important venue for political communication and engagement. In particular, Twitter lowers the cost of entry for political activity, with the result that millions of people follow and interact with political elites online. However, most studies of the political uses of twitter focus on the substance and content of tweets themselves. In contrast, we ask what influences the rates at which users engage with the tweets posted by political elites. To do this, we obtained the number of likes and retweets for each of President Trump's tweets over a 14-month time span. Using these data, we find first that engagement varies with Trump's net approval in the broader electorate. Second, we find that engagement varies with the substantive content of the tweet: negatively toned tweets and tweets involving foreign policy receive higher levels of engagement than other tweets. Third, we find that high-salience events-for example, the recusal of Jeff Sessions-lead to more engagement. Fourth, we find some evidence that engagement levels vary with the timing of the electoral cycle. Overall, we argue that the factors influencing Twitter engagement are in some ways similar to the factors influencing political activity more broadly, though it is possible that the fact that Trump's use of Twitter is unique among politicians drives some of our results.
