Marx’s Utopia is an immanentized, existentialized NOW; not some future event, per se. In other words, Marx’s atheism collapsed what ought to be 
into what is, and then asks that people make what is what ought to be. Utopia is a deification of the material processes, as those are enacted by the socialized agents in that process, wherein there is equity and equality for all. It is an existentialized (not simply actualized) eschatological vision of the way the world ought to be, in contradiction to what is; when what is, is a corporatocracy rigged for the 1% to enrich themselves off the backs of the other 99% (to put this in contemporary terms). So, to speak in Christian tongue: Marx is not concerned with the future, but with the future as the present; since that’s all we have as immanentized agents ensconced in the material processes of a physicalized world. As such, without Christ as the telos and centraldogma of all creation, it is up to those left behind to the brute dialectic of materialization to irrupt an actualized eschaton that only a deified, a Messianic humanity can imagine (based upon its submission to material processes) and enact. Since it isn’t a future reality, since for Marx future realities are mythos that the weak might need, the Utopia must come now; or it will come now, once people come to this naturalized recognition of how things ought to be, in contradistinction to what currently is (in a Capitalized and Classified state)—this will be the time of the ‘second coming.’ Terry Eagleton describes Marx’s inklings on Utopia and a future eschaton this way:
There are, as it happens, far more interesting uses of the word “utopia” in the Marxist tradition. One of the greatest English Marxist revolutionaries, William Morris, produced an unforgettable work of utopia in News from Nowhere, which unlike almost every other utopian work actually showed in detail how the process of political change had come about. When it comes to the everyday use of the word, however, it should be said that Marx shows not the slightest interest in a future free of suffering, death, loss, failure, breakdown, conflict, tragedy or even labour. In fact, he doesn’t show much interest in the future at all. It is a notorious fact about his work that he has very little to say in detail about what a socialist or communist society would look like. His critics may therefore accuse him of unpardonable vagueness; but they can hardly do that and at the same time accuse him of drawing up utopian blueprints. It is capitalism, not Marxism, that trades in futures. In The German Ideology, Marx rejects the idea of communism as “an ideal to which reality will have to adjust itself.” Instead, he sees it in that book as “the real movement which abolishes the present state of things.”
Just as the Jews were traditionally forbidden to foretell the future, so Marx the secular Jew is mostly silent on what lie ahead. We have seen that he probably thought socialism was inevitable, but he has strikingly little to say about what it would look like. There are several reasons for this reticence. For one thing, the future does not exist, so that to forge images of it is a kind of lie. To do so might also suggest that the future is predetermined—that it lies in some shadowy realm for us to discover. We have seen that there is a sense in which Marx held that the future was inevitable. But the inevitable is not necessarily the desirable. Death is inevitable, too, but not in most people’s eyes desirable. The future may be predetermined, but that is no reason to assume that it is going to be an improvement on what we have at the moment. The inevitable, as we have seen, is usually pretty unpleasant. Marx himself needed to be more aware of this.
Foretelling the future, however, is not only pointless; it can actually be destructive. To have power even over the future is a way of giving ourselves a false sense of security. It is a tactic for shielding ourselves from the open-ended nature of the present, with all its precariousness and unpredictability. It is to use the future as a kind of fetish—as a comforting idol to cling to like a toddler to its blanket. It is an absolute value which will not let us down because (since it does not exist) it is as insulated from the winds of history as a phantom. You can also seek to monopolise the future as a way of dominating the present. The true soothsayers of our time are not hairy, howling outcasts luridly foretelling the death of capitalism, but the experts hired by the transnational corporations to peer into the entrails of the system and assure its rulers that their profits are safe for another ten years. The prophet, by contrast, is not a clairvoyant at all. It is a mistake to believe that the biblical prophets sought to predict the future. Rather, the prophet denounces the greed, corruption and power-mongering of the present, warning us that unless we change our ways we may well have no future at all. Marx was a prophet, not a fortuneteller.[1]
If you think that what we are seeing in the streets of America, and all across the Western globe isn’t a Marxist enactment of an eschatological hope, you’d be sort of silly, wouldn’t you be? We are in the midst of Marx’s immanentized vision of the world enacted on the backs of the ‘useful idiots.’ Black Lives Matters (the organization), Antifa, and a plethora of other well-funded (and now by a national shakedown) leftist organizations are the useful idiots Marx knew were necessary if the sort of revolution he believed would just ‘naturally’ arise were to ever become an actuality. We have seen Marx’s vision beatified over and again in the 20th century; it never turns out well. How could it? When the center of the revolution is an abstract humanity from the risen Christ’s humanity for us, all the world ends up with is hell; rather than heaven on earth.
[1] Terry Eagleton, Why Marx Was Right (New Haven&London: Yale University Press, 2011), Loc 774, 782, 790, 797 kindle version. Eagleton characterization of Hebrew prophets is inaccurate, by the way; they did foretell as well, they didn’t just forthtell.