Blocking the Radical Right: Evidence from Strategic Candidate Voting Against the AfD in Germany’s 2025 Federal Election

Abstract This paper examines strategic candidate voting against radical-right parties, focusing on the Alternative for Germany (AfD) in Germany’s 2025 federal election. Germany has long been considered “hard ground” for radical-right parties, yet the AfD has expanded rapidly over the past decade and, in 2025, fielded numerous highly competitive district candidates, raising concerns about potential AfD direct mandates. Against this backdrop, we investigate whether mainstream voters coordinated their candidate choices to prevent these candidates from winning. In a first study, we analyze district-level election results to assess how the strength of AfD candidates shapes patterns of candidate-vote competition. Stronger AfD contenders are associated with a lower number of effective candidates and with notable overperformance of the leading non-AfD candidate, especially in closely contested districts. In a second study, we combine district results with survey data from the German Longitudinal Election Study and estimate multilevel models to test whether voters cross partisan lines under competitive threat. The analysis confirms that voters are willing to support the most viable non-AfD candidate in districts where the AfD is particularly strong, thus providing direct evidence of strategic candidate voting at the individual level. Overall, our findings show how variation in the local strength of AfD candidates shapes strategic coordination among voters, with more competitive districts generating stronger support for the leading non-AfD alternative.