France: 2nd Republic survives (presumably Napoleon III dies early), still loses to Germany as the latter coalesces into an Empire, and France goes Red in 1870-1 (Marx or Proudhon or Bakunin?) Maybe you could find a way to do it in the 1870s (3rd Republic gets off to a terribly bad start, maybe by inviting Henri de Bourbon to reign as Henri V and then going Red when Henri turns out to be a Very Bad Monarch?).
England: Victoria plunges into an even deeper depression on the death of Albert and withdraws from political life altogether. Conservatives of the slightly loony stripe (Palmerston?) take control of the government instead of conservatives of the basically sensible sort (Disraeli). Ireland and frustrated Chartists boil over and a Republic is declared; it drifts Leftward to be Marxist before the turn of the century.
Russia: The Polish rebellion of 1830 is more successful - not in liberating Poland from Russia, but simply in dragging the war out longer - even 1834 would be long enough. Bakunin remains in the Russian Army instead of deserting out of boredom and modifies his syndicalism to include a strong permanent state instead of being anarchist. Bakuninists seize control of Russia during the rather troubled reign of Alexander II (1888?).
Germany and/or Austria: somehow have Russia thoroughly occupied in 1848 so that it cannot relieve conservative forces abroad. Mitteleurope becomes a mess, but I bet you get a Red statelet or two out of it.
Your major problem is that the theorists behind revolutionary socialism are still alive and working in the time period you're talking about. Marx had been dead for 20 years when Lenin got going, so he could refer to Marx's writings as fixed holy writ without the threat of Karl going "actually, I've thought better of that lately..." A revolution this early almost has to practical and pragmatic with limited demands (Chartism, constitutional vs absolute monarchy, etc) and then drift leftward later. It won't be ideological on day 1 because the ideologies are still being worked out.