The only ones who will come to Christ/believe in Him for all Salvation will be His Sheep Jn 10:26. And its not by their own freewill nor anything native or natural within them, but by the Father having given them to the Son Jn 6:37,65 175which speaks to Election. The Father by drawing them to Christ, actually, by His Spirit of Grace, causes them to come or believe in Christ, hence all credit, praise, honor must go to God for a person believing in Jesus Christ for Salvation. See Phil 1:29
For unto you it is given on behalf of Christ, not only to believe in Him, but also to suffer for His sake,