We propose a novel measure of voter ideology and study the (socio-economic) determinants of political beliefs. We examine the dimensionality of contemporary voter ideology using survey data of a representative sample of Dutch citizens. Using factor-analyses, we identify and validate four relevant dimensions that capture (1) preferences for economic equality, (2) preferences for markets and efficiency, (3) preferences for personal and cultural freedom, and (4) nationalist, protectionist and populist preferences. We continue with a regression analysis on the determinants of multidimensional voter ideology and compare these to the determinants of the traditional left right measure of ideology. We find that there is substantial heterogeneity in the determinants of political preferences. Moreover, using a one-dimensional left-right representation of voter ideology conceals most of this heterogeneity.