While it is rather common in the US context to think of an exclusive attachment towards either the Republican or the Democratic party, this is less clear for European multi-party systems where it is possible and likely that citizens could develop attachments towards more than one party. With the recent integration of a new measurement instrument for capturing multiple party attachments in the GESIS panel, a mixed-mode representative survey for Germany, we now have a validated instrument and representative data to further investigate in which combinations multiple identifications occur and how they could be explained. Our results show that about 30 percent of the respondents (and half of all party adherents) have multiple party identifications. Therefore multiple attachments are a frequent phenomenon in Germany. Furthermore, attachments within political camps are more common than between political camps.
For an explanation of multiple attachments, we used the concepts of political involvement and sociological cross-pressures. The indicators that we have deduced from these concepts are theoretical and empirically proven to be causally prior to party identification and could therefore serve as possible determinants. Based on multinomial logistic regressions, the results of the empirical analyses show that both components of political involvement – education and political interest – have a positive effect on multiple party attachments within political camps. However, no such effect could be found for the sociological cross-pressures. But conflicting group memberships have an effect on multiple attachments between camps, at least when two or more of such cross-pressures are present, whereas political interest and education do not have a significant effect in these cases.
We can infer that party identification might fulfill different functions for different groups of political partisans. For less politically involved voters, single party identification could function in the classical notion as an emotionally based cognitive short-cut, acquired in primary socialization, that acts as a perceptual screen. This is more in line with the perspective raised by Mason (2015) for the US, where political partisans support parties in the same way as sport fans support their teams. However, politically involved voters could feel attached to parties mainly because of instrumental reasons: They feel close to several parties because the parties’ stances agree with their political views.