The Bible says God has chosen us to salvation. But does that mean free-will has no part in it?
Jesus said, "Many are called but few are chosen." But I think we need to redefine what it means to be chosen, because notice Jesus didn't say, "Many are called, but few CHOOSE." Instead He said, "Many are called but few are CHOSEN." So there are two types of people mentioned here: the called, and the chosen. And in-between these two states of being is our individual response to the call (the parable of the wedding feast makes that clear). Our acceptance of the call is factored-in to our being chosen.
So which came first, our individual response, or our chosenness? Paul said, "Whom He did foreknow, he also did predestinate..." Notice that a person is not predestined on some arbitrary basis: rather, he is predestined based on God's foreknowledge. Foreknowledge doesn't mean God makes it happen: foreknowledge means God simply knows ahead of time what we will do. So although our response to the call of the Gospel is a factor in our being chosen, God already knew us, and therefore it can be said that He chose us in Him before the world began.