Partisan sorting is deepening ideological disagreement in many societies worldwide by
distributing beliefs exclusively along the party lines. In this study, I focus on the product of
sorting, partisan issue alignment. In the cross-sectional analysis, I assess the party system and
party-related explanations through multi-level models and belief network system comparisons.
Using the eighth wave of the European Social Survey, I show that radical right and new left
party supporters are those most aligned with their party ideology. However, the effect is lesser
for the radical right partisans due to the lower belief constraint and different organization of
beliefs. In contrast with previous reliance on party polarization, I found no effect of party
system characteristics. Finally, I present evidence that three aspects of party ideological
positions (extremity, lack of blurring and nicheness) contribute to higher alignment. However,
results indicate heterogeneity depending on the issues at stake.
