Do most Christians go to hell? Well, considering I am a man who is subject to many faults and errors it is unwise for me to say who will be or not be in Heaven. Only the omniscient God knows who will be among the Blessed in Heaven. However, there are several scriptural passages that can help us know the type of people who will be among the Damned as opposed to the Blessed.
For one, a person must be regenerated and born again according to the text, “Verily, verily, I say unto thee, Except a man be born again, he cannot see the kingdom of God.” (John 3:3). If a person has not participated in the “washing of regeneration” (Titus 3:5) they are in a state of damnation. Thus we can conclude that those who are without the Spirit of God and are not justified through faith in His Son will not participate in the Beautific Vision if they die in that state.
Secondly, what about those who profess to be believers? Well, according to our Lord, not all those who profess to be believers shall be welcomed to the Heavenly Haven according to the text, “Not every one that saith unto me, Lord, Lord, shall enter into the kingdom of heaven; but he that doeth the will of my Father which is in heaven. Many will say to me in that day, Lord, Lord, have we not prophesied in thy name? and in thy name have cast out devils? and in thy name done many wonderful works? And then will I profess unto them, I never knew you: depart from me, ye that work iniquity.” (Matthew 7:21-23). Along with verses 13 and 14 of that same chapter we can also conclude that few will enter into Paradise, “Enter ye in at the strait gate: for wide is the gate, and broad is the way, that leadeth to destruction, and many there be which go in thereat: Because strait is the gate, and narrow is the way, which leadeth unto life, and few there be that find it.” (Matthew 7:13-14). With this we know that these people were not true believers since true believers are those who are justified by faith and prove their justification by their obedience (1 John 2:3-4), love to the brethren (1 John 3:14-15), and their mortification of sin (1 John 3:9-10). It is then reasonable to conclude that those who are among the Blessed are those who are made righteous through faith in Christ. It would seem that if there was a person who professes to be a Christian and yet lives in unrepentant sin he would be in a state of damnation. However, if there was a person who claims to be a Christian and yet bears the fruit of righteousness and love he has upon his soul a moral persuasion to believe he will be saved.
To answer your question then, “Do most Christians end up in hell?” I would have to say that no person who is a true Christian will end up in hell if he dies as a true Christian. However, if someone is a false believer he won’t be in heaven based upon many texts (1 Cor 6:9-11, Gal 5:19-21, 1 John 3:10).
On a side note, I’m not denying justification by faith alone. I am merely saying that a person who is truly justified by faith will evidence his justification by his deeds.