I don't know where you heard that. The media keeps reporting that Russia is losing the war, or may be losing it,* but that it is likely to drag on for a long time. No one that I have heard from since the first weeks of the war has ever said or implied that it was about to end.

* As Russia changes its aims, the definition of "winning" changes. This is a separate way Russia can win: declare victory with whatever territory you have seized and call for peace negotiations.