ABSTRACT Do negative campaigning strategies evolve in sync with a party leader’s position in public opinion polls? In Germany’s multi-party system, previous research during the traditional media era found that a chancellor candidate’s drop in the polls did not impact negativity. This study focuses on the dynamic campaign in the 2021 Federal Election, which is the most competitive campaign to date in the social media era as there was no incumbent chancellor candidate. The prevalence of negative campaigning by six major party leaders who made a total of n = 3580 posts on Facebook and Twitter from 1 March to Election Day on 25 September 2021 is studied here. Negative posts accounted for 7.7 per cent of total posts. Results also show that a chancellor candidate’s position in the polls matters: Front-runners are less likely to rely on negative campaigning, but as candidates drop down in the polls from being the main challenger to rank third or lower, their negative campaigning increases. During the official six-week campaign or the hot phase, the number of negative posts increases overall as Election Day approaches. Variation in the use of negative campaigning among the individual chancellor candidates is discussed as is evidence of negative campaigning prior to the hot phase.