AHC: Spartacist Revolt Succeeds

How do you make the Spartacist revolt of 1918-1920 in Germany turn into a full-blown, successful Communist revolution?
 
More support by the Social democrats (improbable, but for a while the SPD and the Socialist USPD governed together), and/or the Red Army defeating Poland.
 
Pretty much all the points that need to happen to give it a chance:

1. The "Spartacist Revolt" in January 1919 doesn't actually happen, it was a disaster basically forced on them by the SPD.
2. Rosa Luxemburg survives, without her there isn't a leader who can do it.
3. The Spartacists merge with the shop stewards' movement, bringing together the two most active radical groups in Germany at the time.
4. The Spartacists / KPD win over some of the workers' councils.

To pull it off, you need a little luck (no Rosa getting killed by Freikorps) and a much better organization (the Spartacists would need to have been built better from the time of the Zimmerwald conference in 1915). Then you could've led into a confrontation later, on the KPD's terms, with better results as workers are fairly quickly disillusioned from the Weimar Republic and the KPD are in much better place to exploit this. The art of revolution is really in the timing and a bit of luck.
 
If you mean the Deutschnationaler Handlungsgehilfen-Verband: They were right extremists and antisemites, they'd never have collaborated with the Communists.
 
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