  With social media penetration deepening among both citizens and political
figures, there is a pressing need to understand whether and how political use
of major platforms is electorally influential. Particularly, the literature
focused on campaign usage is thin and often describe the engagement strategies
of politicians or attempt to quantify the impact of social media engagement on
political learning, participation, or voting. Few have considered implications
for campaign fundraising despite its recognized importance in American
politics. This paper is the first to quantify a financial payoff for social
media campaigning. Drawing on candidate-level data from Facebook and Twitter,
Google Trends, Wikipedia page views, and Federal Election Commission (FEC)
donation records, we analyze the relationship between the topic and volume of
social media content and campaign funds received by all 108 candidates in the
2016 US Senate general elections. By applying an unsupervised learning approach
to identify themes in candidate content across the platforms, we find that more
frequent posting overall and of issue-related content are associated with
higher donation income when controlling for incumbency, state population, and
information-seeking about a candidate, though campaigning-related content has a
stronger effect than the latter when the number rather than value of donations
is considered.
