Answer :

No because they were weak after all they had just started their nation.:)
No-- France and Spain offered money, weapons, naval support, and military training.

Though the Patriots had an ideology to fight for and would have continued fighting the cause even with loss, the win comes from strong European support. France was an important ally providing naval support and official military training which the Continental Army needed. France and Spain also continued to trade with the colonies keeping their economy afloat during the war.