Again not at all what he's advocating. Did you even read the book? I'm not particularly interested in arguing the point at large but if you're going to make the point you should at minimum use quotes that actually agree with you. Lenin’s point in that passage is not “support whatever vaguely left bourgeois candidate is available because the masses are backward”. It is that communists should not abstain from bourgeois parliaments while workers still have illusions in them. The “you” in the passage is communists, organised independently, entering reactionary institutions under their own programme in order to reach workers, expose bourgeois democracy, and build communist influence. That is completely different from backing liberals/progressives/Democrats as the best available option. “Work within reactionary institutions” does not mean “support the candidates produced by those institutions.” It means communists use those arenas as platforms for communist agitation rather than standing outside them.