Replication data for: Sense or Sensibility? Political Attitudes and Voting Behaviour of Party Members, Voters and Supporters of the Italian Centre-Left

This article analyses effect of primary elections on party membership and electoral behaviour. Direct democracy instruments trigger significant modifications in the role and behaviour of grassroots members. The case of the Italian centre-left parties, and particularly the Democratic Party, is in this sense relevant, as for over a decade, they have been reaching out to supporters in order to integrate them into decision-making processes, such as selecting the party leader, candidates or the chief executive candidate. The distinction between members and supporters has become blurred. The article focuses on voting behaviour and party attachment of three different groups of primary voters, namely party members, supporters and external voters. This paper aims to explore the differences among the three groups, particularly with regard to socio-political and ideological profiles, political behaviour and party loyalty. What is the difference between the three groups with regard to voting behaviour and motivations in primary elections? And what is the difference with regard to voting intentions in general elections? We will examine these issues using survey data collected in 2012 during the centre-left coalitions' primary elections. Through this original dataset, evidence can be found regarding the consequences of the differences in the political profiles between members and supporters regarding their voting behaviour and motivations.