Research on the political consequences of terrorism often finds a rally around the flag effect: terrorist attacks, as other types of threats, tend to produce spikes in popularity and support for the incumbent, as citizens turn to those in power seeking protection. Most research, however, is based on single case studies that analyze very salient attacks from international terrorist organizations. Even if these studies are well identified, the question of generalizability remains, as the studied attacks are often very idiosyncratic. In this paper, we explore the rally around the flag effect in an arguably difficult context: a sustained terrorist campaign held by domestic terrorist groups in a parliamentary democracy (Spain). To overcome the limitations of the single-attack studies, we use a multiple unexpected event approach: we developed a systematic process of matching the occurrence of terror attacks during the fieldwork of official public opinion surveys in Spain, through which we identified 142 valid attack-survey pairs. We find that in the attacked region support for the incumbent increases, on average, around 4 percentage points right after an attack, while support for the opposition decreases in a similar amount. These effects seem to occur mostly for the conservative incumbent and are especially relevant for the attacks that target civilians. We use a survey experiment to provide additional evidence in support for our interpretation of the findings.