The elect were purposed unto salvation (2 Thes. 2:13) through elected means and application. There is no atonement that stands isolated from other aspects of God's salvation of the elect and made to stand by itself. Hence, the question of potential versus actual is oxymoronic.
God's purpose of election saves no one but is "to" salvation (2 Thes. 2:13) which is THROUGH sanctification of the Spirit AND belief of the truth. Hence, God's purpose of election ACTUALLY saves N

NE because His purpose cannot be isolated from its actual provision and actual application. When you isolate it and make it to stand alone you repudiate it completely and make it oxymornic as His Purpose has NO REALITY from its provision and application. Hence, you cannot separate, isolate any of these aspects from the others without repudiating it completely.
The actual provision of Christ's life and death cannot be isolated and made to stand alone. Apart from God's purpose it has no application to anyone. Apart from its application it has no PURPOSE or PROVISION for anyone.
He purposed to save the elect. He provided to save the elect, but until He actually saves the elect His purpose is unfulfilled and they are unredeemed.