Incumbency Effects in the German Mixed-Electoral System

Research question/goal: 

The literature on incumbency effects finds vote premiums for incumbent candidates in various institutional contexts. It has been shown that incumbency effects vary over electoral systems, with larger effects in single-member districts than in closed-list systems. In mixed-member electoral systems, however, incumbency can mean different things: having won the local district race in the first-past-the-post (FPTP) tier or having entered parliament via the party list in the proportional representation (PR) tier. Notably, in the German compensatory those two categories are not disjunct. What is the electoral benefit of each type of incumbency in the German mixed-member system? Are the effects only relevant to the respective tier, or do they spill over to the other tier? And how do these effects combine when PR incumbents simultaneously run in local district races, and vice versa? The project investigates those questions by analysing German federal elections from 1953 to the present.

Current stage: 

During the last year, we conducted analyses on the effects of different incumbent categories on the candidate vote in the majority segment as well as on party list votes in the proportional representation segment. The results confirmed that local incumbents generate bonus votes for the party list. Furthermore, this positive effect was shown to be at the expense of the other major party and not of the smaller potential coalition partners. This insight is new and suggests that incumbents have a majority-building effect in the mixed electoral system without simultaneously counteracting fragmentation of the party system. The results will be published in 2021 in a monograph on the German mixed electoral system.

Fact sheet

2018 to 2021
Data Sources: 
Information on candidates for Bundestag elections from official sources
Geographic Space: