I asked similar thing not long ago. Here goes my two cents; after making peace with germans in the manner of Brest Litovsk you have the tsar who empowers a clique of extremist and nationalist members of of the army, Wrengel comes to mind. Combine that with pointing some true hard line reactionary for the prime minister, like Vladimir Purishkievich who was outright fascist who publicly called for shooting of socialists everywhere and was the founding member of first russian fascist group Black Hundreds. Dissolve Duma, proclaim martial law and shoot every socialist, liberal and opposition politician you can find.
Then start shooting the rebellious part of population and disloyal regiments of the army, not letting them have the chance for launching armed response or getting too organized for that matter. In the end you have your classic right wing dictatorship/monarchy which could easily survive the till modern day by banding together with her global fellow dictators and propping them up as USSR did ITT. After all, there is never a shortage of right wing dictatorships in the world.