In Western Europe and America, parliament has become most odious to the revolutionary vanguard of the working class. That cannot be denied. It can readily be understood, for it is difficult to imagine anything more infamous, vile or treacherous than the behaviour of the vast majority of socialist and Social-Democratic parliamentary deputies during and after the war. It would, however, be not only unreasonable but actually criminal to yield to this mood when deciding how this generally recognised evil should be fought. In many countries of Western Europe, the revolutionary mood, we might say, is at present a “novelty”, or a “rarity”, which has all too long been vainly and impatiently awaited; perhaps that is why people so easily yield to that mood. Certainly, without a revolutionary mood among the masses, and without conditions facilitating the growth of this mood, revolutionary tactics will never develop into action. In Russia, however, lengthy, painful and sanguinary experience has taught us the truth that revolutionary tactics cannot be built on a revolutionary mood alone. Tactics must be based on a sober and strictly objective appraisal of all the class forces in a particular state (and of the states that surround it, and of all states the world over) as well as of the experience of revolutionary movements. It is very easy to show one’s “revolutionary” temper merely by hurling abuse at parliamentary opportunism, or merely by repudiating participation in parliaments; its very ease, however, cannot turn this into a solution of a difficult, a very difficult, problem. It is far more difficult to create a really revolutionary parliamentary group in a European parliament than it was in Russia. That stands to reason. But it is only a particular expression of the general truth that it was easy for Russia, in the specific and historically unique situation of 1917, to start the socialist revolution, but it will be more difficult for Russia than for the European countries to continue the revolution and bring it to its consummation. I had occasion to point this out already at the beginning of 1918, and our experience of the past two years has entirely confirmed the correctness of this view. Certain specific conditions, viz., (1) the possibility of linking up the Soviet revolution with the ending, as a consequence of this revolution, of the imperialist war, which had exhausted the workers and peasants to an incredible degree; (2) the possibility of taking temporary advantage of the mortal conflict between the world’s two most powerful groups of imperialist robbers, who were unable to unite against their Soviet enemy; (3) the possibility of enduring a comparatively lengthy civil war, partly owing to the enormous size of the country and to the poor means of communication; (4) the existence of such a profound bourgeois-democratic revolutionary movement among the peasantry that the party of the proletariat was able to adopt the revolutionary demands of the peasant party (the Socialist-Revolutionary Party, the majority of whose members were definitely hostile to Bolshevism) and realise them at once, thanks to the conquest of political power by the proletariat—all these specific conditions do not at present exist in Western Europe, and a repetition of such or similar conditions will not occur so easily. Incidentally, apart from a number of other causes, that is why it is more difficult for Western Europe to start a socialist revolution than it was for us. To attempt to “circumvent” this difficulty by “skipping” the arduous job of utilising reactionary parliaments for revolutionary purposes is absolutely childish. You want to create a new society, yet you fear the difficulties involved in forming a good parliamentary group made up of convinced, devoted and heroic Communists, in a reactionary parliament! Is that not childish? If Karl Liebknecht in Germany and Z. Höglund in Sweden were able, even without mass support from below, to set examples of the truly revolutionary utilisation of reactionary parliaments, why should a rapidly growing revolutionary mass party, in the midst of the post-war disillusionment and embitterment of the masses, be unable to forge a communist group in the worst of parliaments? It is because, in Western Europe, the backward masses of the workers and—to an even greater degree—of the small peasants are much more imbued with bourgeois-democratic and parliamentary prejudices than they were in Russia because of that, it is only from within such institutions as bourgeois parliaments that Communists can (and must) wage a long and persistent struggle, undaunted by any difficulties, to expose, dispel and overcome these prejudices.

The German “Lefts” complain of bad “leaders” in their party, give way to despair, and even arrive at a ridiculous “negation” of “leaders”. But in conditions in which it is often necessary to hide “leaders” underground, the evolution of good “leaders”, reliable, tested and authoritative, is a very difficult matter; these difficulties cannot be successfully overcome without combining legal and illegal work, and without testing the “leaders”, among other ways, in parliaments. Criticism—the most keen, ruthless and uncompromising criticism—should be directed, not against parliamentarianism or parliamentary activities, but against those leaders who are unable—and still more against those who are unwilling—to utilise parliamentary elections and the parliamentary rostrum in a revolutionary and communist manner. Only such criticism—combined, of course, with the dismissal of incapable leaders and their replacement by capable ones—will constitute useful and fruitful revolutionary work that will simultaneously train the “leaders” to be worthy of the working class and of all working people, and train the masses to be able properly to understand the political situation and the often very complicated and intricate tasks that spring from that situation.

There is Lenin's take in 1917 for anyone curious: https://www.marxists.org/archive/lenin/works/1920/lwc/ch07.htm

But, it is immaterial to conflate parliamentarian institutions between nations, let alone over a century of time which has passed. Lenin was endorsing a communist party's participation within parliament and while many EU nations do have communist representation (often disparaged, which I won't be commenting on) it is clear that there is no coherent communist representation in the US. This is likely by design because of Lenin's above observation; the US doesn't want to allow free publicity to an earnest communist party so it de facto bars them from participating unofficially by preventing them from organizing into a party.

Let it be clear that Lenin would not agree that the Democrats are worth voting for. As he clearly states here:

"To attempt to “circumvent” this difficulty by “skipping” the arduous job of utilizing reactionary parliaments for revolutionary purposes is absolutely childish. You want to create a new society, yet you fear the difficulties involved in forming a good parliamentary group made up of convinced, devoted and heroic Communists, in a reactionary parliament! Is that not childish?"

Endorsement of democrats is simply a way to "feel" like you're putting the work in without actually doing so - the democrats are anti-communist, if that wasn't obvious to someone, therefore they will hamper gains of the proletariat to the same extent as republicans - simply with different rhetoric and "rationale" - as Lenin puts it, "for the purposes of duping the masses".

Lenin was in favor of meaningful participation in reactionary institutions but the US has absolutely terminated the ability for meaningful participation by a communist party. Is it not clear by the fact that the average person cannot even begin to accurately define communism? The high-profile democrats branded as "Marxists" are painted as simple welfare-state proponents and denounce AES states.

So, if boycotting the elections isn't effective, as Lenin advocates, and they can no longer be used in a materially effective way by a coherent Communist party - then how is the publicity and fervor of elections to be used strategically in the digital age? I'd advocate running leftists as independents and just leave it at that - have a clear leftist policy platform and try to go about harm-reduction by stealing a few seats from both parties where possible. But, elections largely serve to exhaust the political ambitions of the working class - encapsulating it within a harmless farce rather than allowing it to manifest into a dual-power structure akin to the soviet system.

The real work to be done right now with the conditions as they are is off-camera building dual-power structures be they unions, soviets, literacy programs, etc - and most importantly these institutions need to be protected at all costs from infiltration so that they can serve as bodies which provide political education/organization to those involved within them. To prevent infiltration a lottery style leadership should be employed, imo.

The best part about dual-power institutions is that the people whom they comprise get to establish the arbitrary rules, processes, and decorum; contrast this to how nominal socialists operating within the DNC get routinely shafted by rules which were imposed upon them by the capitalist class which controls the party apparatus.