TikTok has shifted from a once marginal entertainment platform to an important channel of parliamentary communication, yet we still know little about who uses it intensively and why. We identify three sets of potential drivers: party incentives, behavioural persistence, and individual characteristics. Our analysis builds on a novel data set comprising the complete posting histories of all Members of Parliament (MPs) in Germany and the United Kingdom, covering activity from MPs’ first adoption in 2020 through the end of 2024 and linked to party- and individual-level characteristics. We combine descriptive analyses with zero-inflated negative binomial models with year fixed effects. Three findings stand out: First, party nicheness, a relational measure of the degree to which a party focuses on issues not emphasised by other parties, predicts higher posting volumes, with MPs from such parties producing more content than mainstream parties. Second, TikTok use is path-dependent: once MPs establish high (or low) posting levels, they tend to sustain them over time. Third, individual traits matter unevenly: prior platform experience and gender are associated with higher activity, while age and institutional position show no consistent effects. Our results shift the focus from stylistic repertoires to structural drivers of elite communication on TikTok and demonstrate that sustained activity is concentrated, persistent, and above all shaped by party incentives. The findings suggest that TikTok lowers entry barriers and expands political visibility, potentially re-engaging voters, yet its dynamics may also amplify polarisation by disproportionately incentivising fringe actors to be active on the platform.
Huber et al. (2026) studied this question.