Depends on the protestant branch, I'd heard repentance defined as "turning away from sin 100% and leaving it behind" but that kind of theology gets mixed up in "faith not works" and the idea that if you haven't immediately asked forgiveness for every little time you mess up you're going to hell until you do. Swear while falling down the stairs, then die in your living room? Hell.

Of course there's also the opposite which is "once you accept Jesus there's no possible way you can ever not be saved" which doesn't match up with free will in my opinion.