Recently, scholars have based their explanations regarding support for EU integration on identities and values, generally oversimplifying citizens' self-interest. Conversely, models on redistribution preferences in multi-tier contexts have not tested its micro-level foundations. In this paper, I reconcile both lines by articulating individuals’ preferences regarding the EU through redistributive models where self-interest is determined by i) individuals’ income within their country, and ii) country’s median income within the EU. Thus, I apply this model for the 2004 Enlargement, as the accession of poorer MSs implied an exogenous shock for EU15 MSs’ position within the union –while some remained rich or poor, others suddenly became contributors (rich). I expect support for integration to significantly drop there in comparison to other EU15 MSs. This effect must be distinguished from actual policy changes that enlargement entailed, as eligibility changes of Cohesion Funds. I employ individual data from EES and ESS, and Eurostat country/region statistics. Through a DiD design, I show that countries that remained poor experienced the largest support reduction, while the effect of stop receiving CFs by regions is non-significant.
