We undertake an individual-level analysis of mass political behavior toward sovereign debt resettlement by leveraging the unique circumstances of a 2011 referendum on debt repayment in Iceland. This allows us to engage broader questions about mass international political economy. Against the recent thrust of a growing literature, we find evidence of material economic “pocketbook” effects—self-interest—on voting behavior, operating alongside symbolic/sociotropic and partisan/political logics. Contrary to expectations, these self-interest effects are not conditional on voter sophistication. We conclude that conventional sampling frames may be inappropriate for understanding contemporary democratic contestation over international economic policy.