Differential representation? The gaps between mainstream and niche party representatives and their voters in The Netherlands

This paper investigates the differences in the representational performance of mainstream and niche parties. It hypothesizes that mainstream parties represent their voters better on the socio-economic dimension and issues, while niche parties represent their voters better on the socio-cultural dimension and specific socio-cultural issues. To test these expectations, the congruence between Dutch local representatives of both mainstream and niche parties and their voters is measured using two surveys, one among Dutch voters and one conducted by the authors among a representative sample of municipal councillors. By analysing ‘many-to-many’ scores of congruence, which compare the distributions of the preferences of the representatives and their voters, it is concluded that mainstream parties do not consistently represent their voters better on specific issues or dimensions than niche parties, or vice versa. Instead, a mismatch between the preferences of representatives and their voters sometimes occurs particularly on issues that a party ‘owns’, because representatives tend to take more radical positions on these issues than their supporters.