Populism has been defined as a thin-centered ideology that may appear in combination with different full-fledged host ideologies. A comparison of the recent successful populist parties in Europe and Latin America clearly shows that populism can be found on either side of the left-right dimension and adopt a wide range of different political stances (Mudde & Rovira Kalwasser 2013). In recent years, left and right populist parties have even coexisted in some European countries. Although a considerable amount of literature has been devoted to subtypes of populist parties, much less is known about the different expressions of populism at the level of public opinion. This paper examines the different ways in which people’s populist attitudes are combined with positions on the basic ideological dimensions and various key attitudinal domains. Drawing on an online survey conducted in nine European countries, we use finite mixture models to analyze how individual levels of populism, as measured using the scale developed by Akkerman, Mudde & Zaslove (2014), are linked to economic left-right values, authoritarian-libertarian values, support for European integration, and attitudes towards migrants, employing voting behavior as auxiliary evidence. Results show that, while the configuration of national party systems and the type of populist parties present in each context appear to shape largely the attitudinal patterns of populist voters, there exists substantial variation in ideological expressions of populism not only across countries but also within them that cannot be accounted for only on the basis of supply-side factors. Our findings contribute to a better understanding of the role of demand-side factors in explaining the varying electoral performance of right/left populist parties across countries.