The Bundestag elections of 2009 meant a crushing defeat for the German social democrats and at the same time a low point in electoral turnout. Neither the level of turnout nor the support for the SPD has fully recovered in the last federal election of 2013. In fact, a long term comparison of changes in turnout and changes in the support for the SPD suggests that both are linked especially during the last few decades. The proposed paper tracks down this link to level of individual voting behaviour and voting intentions. Using Data from German election studies and the German General Social Survey (ALLBUS), it shows that the propensity for electoral turnout has been in decline particularly in the traditional core group of SPD voters, the members of the industrial working class. It further shows that a decline in subjective political efficacy is unlikely to be a cause of this decline, while political dissatisfaction with the personal economic situation appears to play a more important role. Finally, the paper discusses the implications of these findings for the role of social divisions in electoral behaviour.