Localised impacts on Islamist political mobilisation in Indonesia: Evidence from three sub-provincial units

What explains the regionally varying electoral outcomes of Islamist parties in Indonesia, the world's largest Muslim democracy? By employing a three-stage approach inspired by Evan Lieberman's nested analysis, this article aims to gain a better understanding of how adaptability to local political contexts matters in determining the vote share of the Islamist Prosperous Justice Party (PKS) at the sub-provincial level. It uncovers that PKS’ electoral mobilisation in non-Javanese regions depends more on whether the party leverages a strong predisposition towards personal votes underpinned by pre-existing clientelistic ties. In contrast, the PKS support base in Java tends to be embedded in specific milieus shaped by deep-seated sociocultural cleavages. The findings thus not only demonstrate the limitations of programmatic, institutionalised parties like PKS in the Indonesian context, but also resonate with a larger body of broader literature on politics in the Muslim world, indicating strategic considerations of local political conditions as an important factor in electoral support for political Islam.