Federal-level Government Participation and State-level Electoral Performance: A Party-based Analysis of Land Elections in Germany, 1949–2017

To what extent does the federal political arena contaminate the regional one in Germany? Does a party’s position as government or opposition on the federal level have a systematic impact on its performance in Land elections? Land elections are often characterised as second order elections, but existing empirical studies that use real election data suffer from important methodological problems. Unlike previous approaches using survey data or comparing vote shares in regional and federal elections, we analyse contamination in two ways. First, we test whether a party’s role at the federal level has a systematic impact on gaining or losing office at the Land level. Second, we examine the vote difference of parties relative to their result in the previous election in the Land. Drawing on a complete dataset of all Land elections from 1949 to 2017, we find confirmation for two phenomena well known in comparative electoral studies. First, the anti-incumbency effect: government parties tend to lose votes. In the German context, as in many other multilevel systems, this is exacerbated by the second effect: contamination. Gaining power or votes on the Land level is very difficult when a party is in government on the federal level.