Even though support for the Danish Social Democratic Party has declined from its historical peaks, it has managed to maintain the stable backing of approximately 25 percent of the voters over the last 15 years. This paper will analyze why the Danish trend for the center-left in general and the Social Democratic Party in particular has differed from the situation in many other European countries over the last 15-20 years (cf. Keating and McCrone 2013). In the framework, six themes have been put forward in order to explain and understand the decline of the center-left in Europe. They comprise the following: 1) The objective decline of the working class milieu and the resulting membership level of trade unions. 2) The unclear positioning of the center-left toward globalization and increased international competition. 3) The lack of organic linkage between the leadership of the Social Democratic Party and the working class. 4) The unclear agenda of the Social Democrats concerning the welfare state. 5) The refusal of the Social Democrats to acknowledge the negative effects of immigration. 6) The center-left support of European integration without fully recognizing its negative impact for workers. Because the center-left of Denmark has not declined, the arguments in this paper are to a certain extent concentrated on explaining why these themes have not contributed to its weakening.