Political Competition and Party Incumbency : The Case of German Federal Elections

Sammanfattning: This paper investigates party incumbency advantage in German federal elections. I use a sharp regression discontinuity to exploit the firstpast-the-post voting system on the first ballot electing district representatives to the Bundestag, using election results from all voting districts that existed in Germany between 1953 and 2013. I find that being the incumbent party leads to a 1.2 percent increase in vote shares in the following election. This analysis focuses on the most dominant political party during the span of the data, the CDU. Historical analysis reveals the effect to be largest when the political system is stable and lowest at a time where the political structure was experiencing a shift. I do not find evidence to argue that the party incumbency advantage is larger when political competition threatens the potential reelection chances of the incumbent.