Historically, totalitarian revolutions have been driven by the left-wing of the middle class during times when the middle-class (or at least segments of the middle class) is rising on a socioeconomic level but has its political ambitions frustrated by deeply entrench elites. I believe this theory explains the French Revolution as well as the Marxist revolutions from the 20th century as well as any.
Today, in the West, we see that the primary constituency for “totalitarian humanism,” is among the upwardly mobile strata of the middle class, which tends to be highly educated, urban-centered, and with highly cosmopolitan cultural values. The actual proletariat (or today’s “post-bourgeois-proletariat,” i.e. the sinking “working to middle-class” in countries like the US) and the peasanty (or rural, agricultural populations generally) tend to be reactionary.
Within the context of today’s US politics, the “Center” (establishment) is comprised of the neoliberal managerial elites (represented in politics by Democrats like Pelosi and Schumer and Republicans like Romney and McConnell). The right-wing of the Republican Party (both “ultra-conservatives” and Trumpian populists) and others further to the right (white nationalists, Alt-Right, fascists, etc.) represent a coalition or agglomeration of forces that were once dominant but have been losing power for generations (the old-bourgeoisie, the post-bourgeois proletariat, WASP culture, rural culture, traditional religion, etc). While the “turn-back-the-clock” politics of these sectors may be retrograde and self-defeating, many people from these sectors can be very insightful in their critiques of what I call “totalitarian humanism” because they see its growing influence and correctly view it as a threat to their own interests.
The left-wing of the Democratic Party represents a wide range of sectors that collectively comprise the constituency of “totalitarian humanism” including:
-The left-wing of the middle class (predominantly, the urban, professional class)
-The lower strata of the managerial elites (what the neocons’ have called the “new class”)
-Elite and upwardly mobile sectors of traditional minority groups: the civil rights bureaucracy/industry (typically led by the bourgeois sectors within minority groups), “Women’s March” types(Big Pink), the gay rights establishment (Big Lavender), what Norman Finkelstein calls the “Holocaust industry”, the organized atheist movement (secular fundamentalism), rising religious minorities (e.g. bourgeois sectors among Muslim-Americans, Linda Sarsour, CAIR types, or New Age clerics like Marianne Williamson)
-Rising business interests challenging dominant business interests (the green energy industry’s challenge to the fossil fuel industry-Big Green vs. Big Oil- is an obvious example, Big Tech vs. traditional Chamber of Commerce types is another)
-What the Maoists/Third Worldists call the “labor aristocracy” (upper strata working class and the business union bureaucracy)
-Moral entrepreneurs and secular priests responsible for disseminating the ideological values of totalitarian humanism (the SPLC or Tim Wise-types, for example)
There is also the question of where those to the left of the Democratic Party stand in this paradigm. Clearly, groups like the Green Party or DSA share the same basic values as the left-wing of the Democratic Party while rejecting the Democratic Party as an organizational vehicle with which to achieve their goals. The hyper-SJW types found primarily in the academic world and the activist left might be considered ultra-fundamentalist versions of totalitarian, with the Antifa sectors simply representing “totalitarian humanism for sociopaths.” Much of the Anarchist left has been regrettably co-opted and subsumed by these sectors. Historically, the Anarchist left has had a very unfortunate tendency to attach itself to left-wing totalitarian tendencies, only to be subsequently backstabbed and purged.
Interestingly, at least some actual Marxist-Leninist tendencies (predominantly, those with Eurasianist or Third Worldist inclinations) seem to be functioning outside the paradigm of totalitarian humanism and have even embraced some criticisms of the managerial elites which overlap those voiced by the right.