Is there anyone who can know other than God Himself who's heart has been hardened? I can totally relate to what it says here in
1 Timothy 1:15
15This is a faithful saying, and worthy of all acceptation, that Christ Jesus came into the world to save sinners; of whom I am chief.
John 3:16-18
16For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life.
17For God sent not his Son into the world to condemn the world; but that the world through him might be saved. 18He that believeth on him is not condemned: but he that believeth not is condemned already, because he hath not believed in the name of the only begotten Son of God.
Roman 5:8
8But God commendeth his love toward us, in that, while we were yet sinners, Christ died for us.
John 10:9
9I am the door: by me if any man enter in, he shall be saved, and shall go in and out, and find pasture.
John 14:6
6Jesus saith unto him, I am the way, the truth, and the life: no man cometh unto the Father, but by me.
John 1:12
12But as many as received him, to them gave he power to become the sons of God, even to them that believe on his name:
John 3:36
36He that believeth on the Son hath everlasting life: and he that believeth not the Son shall not see life; but the wrath of God abideth on him.
Revelation 3:20
20Behold, I stand at the door, and knock: if any man hear my voice, and open the door, I will come in to him, and will sup with him, and he with me.
The above verses are just a few that I believe show what is necessary to be saved and that everyone is eligible.
2 Peter 3:9
9The Lord is not slack concerning his promise, as some men count slackness; but is longsuffering to us-ward, not willing that any should perish, but that all should come to repentance.