What you might be missing is if you are responding, you have already been saved. It isn't like, God nudges... you act... then your saved. It is more like God saves you the end... Any further action on your part is just a result of your salvation. If it is any other way, than you have a small percentage in your salvation, thus taking some of it away from God. How do you argue around that?
Does the bible say that everyone that "sees" salvation will partake in it? Or does it actually say all will see on the last day, some to everlasting life, and some to everlasting destruction?