Partisan Cueing and Preferences for Contentious European Integration Steps

Can political parties steer public preferences for highly contested issues? European integration has become increasingly politicized, forcing governments to heed constituents’ preferences during international negotiations. Existing research suggests that parties can cue their voters, but it remains unclear whether public opinion responds to partisan cues on contentious, real-world European policies that directly affect national autonomy. To study the effects of in- and out-party cues on public preferences, we conduct a pre-registered information treatment experiment in five countries utilizing real-world treatments that avoid deception, while limiting the problem of pre-treatment. Applied to the case of joint European debt, we find that political parties can shape public opinion on fiscal integration, as both in- and out-party cues affect preferences. While our study focuses on EU politics, it has important implications for research on attitudes towards international cooperation more broadly.