Carthage definitely had to supply a complex theater of operations. But I remember he did get supplies , and once was waiting in a port city for promised supplies that were diverted.

That cost him alliances, and set the tone, for a while , where he had to prove, and keep proving, to others in Italy that he could be a reliable balance to Rome. It definitely changed his campaign, and forced him into battles he rather had avoided.

A lot of his success was advertising to others in Italy that they could depend on him. A lot of the troops and supplies he used were from those allies in Italy.

Also, to change the history all he had to do was delay Roman expansion by a few decades; it was probably set in stone he could not keep an invasion up forever: but organizing a lasting counterbalance, with many Tribes and cities in Italy, using Carthage as a nucleus, was possible.

Rome had plenty of opponents in Italy without him, but they had no good way to unify against Rome without him