Social media services have become areas of political communication. Politicians integrate them in their campaigns, journalists use them as sources and topics, and the public uses them for the discussion of politics. In this, political activities on social media are clearly interconnected with the coverage of politics by traditional media. This article analyzes Twitter messages commenting on politics during the campaign for the 2009 federal election in Germany. It will be shown that the temporal dynamics and content of Twitter messages follow a hybrid logic of political coverage, sometimes following the same logic as the coverage of political actors in traditional news media, whereas in other cases following a logic specific to political expression on the Internet.