I'm not quite sure whether it's possible to built up a fleet big enough to beat both.
I have noticed in last www that at least in terms of ressources ships are redicoulus expensive in comparison to landforces.
I don't know how much of an effect the production of equipment without the necessary ressources is but I've seen that Johan is building up 1.51 destroyers per month with 15 naval factories.
That means that he can produce on destroyer every 18.19 days. With just the cost of oil of that one destroyer he could build over 600 new trucks which he needs much more btw.
But there is still hope for Daniel to building up that fleet!
Both of them clicking like mad to avoid screens they obviously spare for dev-diaries in the future.
I don't see any other reason why they show us like 98% battlemap (a lot of them in russia which is quite boring because the SU is fallen and even I would let do the AI the simple task of just capturing undefended provinces).
Daniel has at least 4 battleships in the queue and
has captured the entire soviet fleet, I guess.