Oskar Lafontaine, a former major figure on the left wing of the SPD, joined the new party officially on 18 June 2005, and became their North Rhine-Westphalia frontrunner for the general election on 18 September 2005. As the necessary steps for a merger with the Party of Democratic Socialism (PDS) could not be taken fast enough, he advocated an electoral alliance with WASG members on the PDS's list, to which the WASG and PDS leaderships in principle agreed on 10 June 2005. The title of this list was The Left Party.PDS, which to this end - as a matter of formality - was adopted by the PDS as its new name, because changing a name was comparatively easy.