This book project began more than five years ago when I handed in my diploma thesis, in which I had found a remarkable break in class voting in unified Germany after the social democratic party engaged in pathbreaking welfare state reform in the electoral term 2002-05. The idea that welfare state reforms may lead to realigning elections came to my mind after considering recent electoral change in other European countries. My then supervisor, Alexander Gattig, suggested that I turn this idea into a PhD project. The Department of Political Science at Aarhus University gave me the opportunity to conduct this project in a stimulating intellectual environment and, later, to turn the PhD thesis into a book. On the journey to complete the research project, I have benefited from the help and good advice of a number of people, and I would like to express my gratitude to them.

First, I owe thanks to my main supervisor, Christoffer Green-Pedersen, and my co-supervisor, Rune Stubager, for their excellent advice, constructive criticism and support when I was writing my thesis. They also helped me integrate into a new academic environment in Denmark and to steer my PhD project at various stages. I also owe special thanks to Herbert Kitschelt, who was my supervisor during my stay as a visiting scholar at the Department of Political Science, Duke University, during the fall semester 2009. He offered many inspiring and stimulating comments and also shaped my research interests beyond the thesis and the later book.

Second, I have to thank my two office mates, Flemming Juul Christiansen and Christian Hjerrild Ovesen, for creating a good and enjoyable daily work atmosphere, and for countless discussions on the project, politics and all kinds of other issues beyond politics.

Further thanks go to the members of the Research Section on Danish Politics and the Comparative Politics Section, of which I am a proud member. They provided me with excellent and inspiring comments and constructive criticism during the various presentations of my research project. The same goes for the group of PhD scholars at the department who provided an intellectually stimulating and ‘hyggelig’ working environment and helped me with the various practical and linguistic aspects of getting settled in a new country. I also owe thanks to various members of staff at the department.