The far-right Alternative für Deutschland (AfD) is a prominent force in contemporary German politics: risking social solidarity, increasing anti-democratic attitudes, and advancing exclusionary policies. Despite mass protests and demonstrations across the country against the party since 2017, approximately one in every five German voters currently state they intend to vote for the party in the next federal election. In this article, we examine the proximity of the AfD to right-wing extremist civil society and the impact of right-wing extremist civil society protests on the party’s electoral performance. Using a novel social network dataset, we show that the AfD has become significantly more entrenched within Germany’s right-wing extremist civil society. We further show that protest by right-wing civil society actors with AfD participation significantly increases the party’s vote share. The findings contribute to the ongoing debate in political science about the role of movements on political parties as they demonstrate that opening the AfD to extremist civil society elements increases its vote share.