Profiling the fence-sitters in New Zealand elections: A latent profile model of political voting blocs

'The undecided voters are a deliberate breed, who take their civic duty very seriously, they're committed, thorough, infuriating, wishy washy, thick-headed, boobs. ' --Mo Rocca, The Daily Show with Jon Stewart, 2000 A key group in any election are those voters who are often called things like fence-sitters, centrists, floating voters, undecideds, swing-voters, independents, or moderates. Despite the fact that they tend to swing elections, the personality, ideological and demographic characteristics of this supposed category of people remains largely unexplored (Mayer, 2008). It is also unclear if this category represents a distinct group (or perhaps many subgroups) and if the group actually votes (Feddersen & Pesendorfer, 1996). Furthermore, the scarce literature in this area focuses exclusively on a group referred to as swing-voters, which includes those who vote erratically and the politically apathetic (i.e., those who express mild or moderate, rather than erratic, support for multiple parties; Dalton, 2006; Mayer, 2007, 2008). Additionally, decreasing voter turnout is an issue in New Zealand (Vowles, 2012) and research on swing-voters, their turnout rates and the different voting blocs comes almost exclusively from America's two-party system (Mayer, 2007). A gap remains in the literature when looking at multi-party systems like New Zealand (NZ) in trying to account for undecided voters or for developing statistical modelling techniques to determine types of voters based on political preference. Mixture modelling, namely Latent Profile Analysis provides an opportunity to uncover these types of voters, where they are, who they are and whether they actually vote. This paper applies recent advances in Latent Profile Analysis (LPA; Lanza, Tan, & Bray, 2013) in a national sample of registered voters to model the different profiles of political supporters. We label these profiles Latent Voting Blocs. Voter Blocs traditionally refer to identifiable cohorts or demographic groups that vote in a homogenous fashion. We apply LPA in a data-driven attempt to profile people's political preferences by modelling systematic patterns in the underlying structure of potential voters' support for political parties. As such, we use the term Latent Voting Blocs (LVBs) to refer to these underlying types of people who express different combinations of support for multiple parties; be it high support for one party, some combination of support and opposition, or moderate levels of support for multiple parties. LVBs thus represent different groups of potential voters who should be oriented to vote for different political parties, as well as those who may be less likely to vote because they express moderate levels of support toward all parties; those who are the focus of this paper: the Fence-Sitters. A mixture modelling approach like LPA is needed to identify different blocs of political support in a multi-party system. In said system, people may support different parties to different degrees, rather than one versus the other. The literature suggests that in multi-party systems, more complex partisan attachments may exist than may be uncovered by a simple left-to-right scale (Breen, 2000; Green, Palmquist, & Schickler, 2002). Additionally, most statistical models of voter types focus on who participants voted for rather than differentiating between support ratings for multiple parties (c.f. Breen, 2000; Gormley & Murphy, 2005; Gormley & Murphy, 2008). Using the three-step distal approach for LPA, we then describe these profiles in terms of demographics, personality, and ideology; without having these covariates inform the model solution (Lanza, Tan, & Bray, 2013). We then use the model to assess the extent to which differences in the proportion of the Fence-Sitter LVB across electorates predicts variation in voter turnout for the 2011 NZ election. The NZ electoral system is organized into 63 general and 7 Maori-specific electorates, or geographical areas of between 55,000 (in the case of some Maori electorates) and 70,000 people. …