Yeah, because only neiberals say to vote! Only a true leftist would be self-defeating! /s
Karl Marx and Friedrich Engels stated in The Communist Manifesto and later works that "the first step in the revolution by the working class, is to raise the proletariat to the position of ruling class, to win the battle for democracy" and universal suffrage, being "one of the first and most important tasks of the militant proletariat". (https://en.wikipedia.org/wiki/Democracy_in_Marxism)
There is something to be said for the idea that you only have two choices, although that is a matter of fact because of the "[c]onstitution…which makes it appear as though every vote were lost that is cast for a candidate not put up by one of the two governing parties." (Engels to Frederick Adolph Sorge, December 2, 1893, in Marx and Engels on the United States (Moscow: Progress Publishers, 1979), p. 333.) We need to change how this works, but that needs to be done through a grassroots movement for local level elections at first. This requires voting and participation.
A revolution almost certainly isn't happening, and it's not going to go the way you want. If it were to happen, it'd be bloody and brutal and you wouldn't enjoy it. Also, it's not exactly guaranteed that the leftists win. If anything, I'd bet against it because the other imperialist nations wouldn't want that to happen.