Alright, here's a new idea that will, if all goes well (3rd time should be a charm), blossom into an attractive, well-endowed TL.

I'm going to lay out some general points and explanations first before refining it and going into specifics.
THE RISE OF NASHIISM IN POST-TSARIST RUSSIA
The failure of the 1916 Brusilov Offensive, the well-executed German and Austro-Hungarian response, and the sudden murder of Tsar Nicholas II by Bolshevik conspirators marked the end for organized Russian war effort and integrity of the imperial state. The Tsar's untimely demise and the string of defeats on the front destroyed what little still remained of the old system. Thousands of soldiers were killed or deserted every day while the Tsarist regime began falling apart exponentially. This was the time of utter desperation, yet who could predict the unseen force manifesting itself in the darkness behind the shadows?
The Tsar had been murdered by a Communist Jew. His heir, Alexei, and the Tsarina came under the influence of a certain mad monk, who in turn had his life taken by a group of nobles. After this, Alexei's reign was delayed indefinitely (the Royal Family was taken into hiding) while the nobles fought amongst one another for power.
As the tsarist power structure collapsed, two forces rose, the Social Democratic Labor Party (Bolsheviks and Mensheviks), which were commonly called "Reds" and the tsarist officals and military remnants, called "Whites". Among the political and bureaucratic rubble, here was no chance for reconciliation between these two enemies, not even with the war still raging. Protests turned into riots, riots turned into battles, and battles turned into civil war. By March 1917, the front had effectively dissolved, with the Germans making less than a half-hearted effort to advance, and the Russians feebly resisting.
Many former Tsarist officers now aligned themselves with the Whites, for that party was more accommodating of their aristocratic mindset. However, the aristocracy no longer existed in concrete form; the civil disorder destroyed it. Only the members of this former elite remained, and they fled it like the sinking ship it was. In particular, the defeated yet prideful military men found themselves preferring the White side, and began to bolster its ranks with their gradual entrance. And with this, the destroyed system made its terrifying resurrection (in future Nashiist propaganda this was a recurring term, called
Voskresyenye).
Seeing the rapid devolution in the state of his home nation, Lenin returned to Russia to launch his Petrograd coup and solidify the Bolshevik position. The slogan "Land, Peace, Bread" was supposed to work wonders in the minds of the weary proletariat. In the meantime, however, the Mensheviks had all but broken off with Lenin's radicalism and formed their own faction, tearing apart the already-ineffectual RSDLP. The opposition of the Mensheviks to the radicals would prove troublesome for the duration of the civil war and ultimately work toward the socialist effort in general.
In theory, it is debated that the Reds, with their promise of reform, should have been the ones to prevail and not the Whites. But reality was different. The Tsar, the Sovereign, had been murdered by a
Bolshevik, right as the Brusilov Offensive took its fateful turn for the worse. Marxism was a German ideology formulated by a Jew. A Jew had killed the Tsar. The Bolshevik Party could not save the Motherland.
No, it aimed to destroyed her.
This and much more was what the Whites, their ranks now saturated by nationalistic, conservative nobles and soldiers, propagated among the masses of illiterate, uneducated, poverty-stricken Russians. There were no overt promises of anything, no land, no peace, no bread, only the powerful, neverending roar to advance the will and wrath of Mother Russia. All of Russia's problems lay in the acts of traitors and subversive elements trying to destroy the
Rodina from within. All of these problems could be surmounted through only the undying faith in the Motherland, God, and a resolve to forever neuter the dark forces of the enemy, wherever and however it materialized.
Lenin's negotiations with the Germans, which ceded all territories west of Russia proper, proved to be his undoing. The Whites saw this as an act of high treason, and moreover, it "proved" that the Bolsheviks were trying to sacrifice the Motherland. The Reds, with all their talk of peace and empowerment of the rowdy, uncivilized proletariat, were simply opening the door for their German masters.
In reality, the Whites knew that lower-class reform was a must and that the end of the war was a good thing since it freed up their armies. It is now known that the Whites did indeed enact many reforms and granted its people a high degree of emancipation in the 1918-20 period, but that this effort was tweaked to focus on the satiation of military families and other key classes. But what they said was wholly different, as is described above. While the Reds may have appealed to people's minds, the Whites appealed to their hearts.
In mid-1918, the Reds had been marginalized. The civil war (or struggle, since it was wholly asymmetrical) did continue, but the Whites had already established a stranglehold on key points in the society, geography and capital of the country.
At this time, the Whites renewed the long-paused war with the Germans, who were now facing strong Allied efforts in the West. Between June and November, a streak of victory after victory was scored, and eventually a favorable peace treaty (which granted Russia the 1914 borders and parts of Austria-Hungary) was reached, replacing the embarrassment of Brest-Litovsk. The soldiers of the White Army were universally hailed as heroes at home. The Reds had failed to bring true peace, but the Whites had preserved gloriously. By now, the Reds had lost all integrity, and their forces were effectively crushed by no later a date than 1920.
Meanwhile, the Whites restyled themselves as "Partiya Nasha", or simply "Nashi", meaning "Our Party" and "Ours" respectively. Members of this group were known as "Nashniki" or "Our people". This marks the birth of the Nashiist movement.
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This is a beta-installment, so as I warned, there are missing details and probably problems everywhere with the premise. I posted this to see if this scenario is at all realistic, since there is, frankly, a lot I don't really know about the state of the Mensheviks or the true potential of Russian nationalism in helping the Whites (Nashiists) overcome the multitude of problems they faced from 1917 on.
EDIT: The major inaccuracies have been solved. The Mensheviks are against the Whites. The Mensheviks have always been against the Whites.
Please read and critque!