According to public opinion data over the past decade, most Americans hold center-left attitudes regarding key economic and social policy issues. Recent polls even show significant support of socialism among American adults, especially self-identified Democrats and the millennial generation. At the same time, the focus of the mass media has been on a widespread right-wing populism, while movements on the left seem to lack political clout. In order to better understand this dichotomy, this book explores relations between organized labor and left-wing parties and movements in America at crucial junctures from the 1870s to the present. Providing fresh insight into current political developments, it highlights emerging alternatives and major challenges facing labor and the left today.