Not really, Darwin was always agnostic believer kinda, and he always went to Church regardless. But I remembered even better comparison regarding Darwin, many of his followers despite saying they're atheist believe in magic, i.e. they think evolution always has to be beneficial in the long-term, they're humanists, loathe eugenics, etc. Darwin was ubermensch-leaning while his followers are total untermensch.

About the Mussolini part, Markie has pretty much nailed it.