@Justice Would you classify them as SocDems?
Maybe I’m wrong to do so (and hopefully the literature will clear it up for me, if so) but I currently see anyone who is to the left of the current “political status quo median” as a suitable ally for the big tent left. Democrats, for example, are currently useful. Even if they will quickly cease to be left of the median (and therefore cease to be suitable allies) as soon as any kind of meaningful leftward momentum is achieved.