Political participation is one of the most central topics for understanding contemporary representative democracy. In the very first sentences of their book, Verba et al. (1995: 1) correctly state that ‘Citizen participation is at the heart of democracy. Indeed, democracy is unthinkable without the ability of citizens to participate freely in the government process’. Through participation citizens voice their grievances and make their demands heard to the larger public; they also make governments accountable and politicians responsive. The venues open for such activities are multiple. Citizens may vote on election day, write letters to their public representatives, or campaign for a political party. They may sign a petition, put a bumper sticker on their car, or join a protest march. Sometimes the expression of their will is more subtle, such as when they donate money to non-profit organisations or even boycott certain products in the supermarket. As noted by Huntington and Nelson (1976: 14), ‘the concept of political participation is nothing more than an umbrella concept which accommodates very different forms of action constituting differentiated phenomena, and for which it is necessary to look for explanations of different nature’.