Victory in a war does not necessarily come from the battlefield. Unless the west increase its support a lot more than the <1% of its GDP currently providing to Ukraine, Russia hold superiority in man power and gear as she is channeling over 40% of its budget to the war.
However, Russia lost all three of its one on one wars in the past century on economic grounds. 1905 to Japan, 1915 to Germany and in 1988 to Afghanistan resulting in the collapse of the Russian governments. If Ukraine keep hitting Russian economy at the rear same time keep resisting Russian advancements, this war will end the same way even sooner IMO.