It won't lead to victory, but more likely to lead to a stalemate that could potentially lead to a negotiated settlement.
Russia's objective has always been total conquest and the elimination of the Ukrainian state. I personally had hoped the status quo we found ourselves in last year would lead to a settlement but both sides believed they could achieve their objectives. The withholding of US aid gave Russians the advantage and confidence they could take the home country which would be appalling for Ukrainian people.
I believe stopping the funding would make the war go on longer and be significantly worse for the civilian population that the Russian state believe don't have the right to even exist.