Here's what one source has to say:
But there are other reasons there are so few atheists and so many Christians. Perhaps Christian apologetics convinces Christians that they are right to believe in God and the Bible. Besides, atheism does not have a good history or at least atheists do not have a good history. Stalin, for example, did far more evil than any Christian ever did.
So it really shouldn't be too hard to understand why Christianity is in the mainstream of society and atheism on the fringe.
If you ask atheists why they are outnumbered, they'll typically explain their being in the minority results from the tendency of people to be irrational and superstitious. They'll tell you that atheism does not offer hope of immortality, miracles, or revelations, and lonely, hurting, insecure people need these things to find a way through life.In 2019, a Pew study found that 65% of American adults described themselves as Christians while the religiously unaffiliated, including atheist, agnostic or “nothing in particular”, is 26%. According to a 2018 Pew report, 72% of the "Nones" have belief in God, a higher power, or spiritual force.
But there are other reasons there are so few atheists and so many Christians. Perhaps Christian apologetics convinces Christians that they are right to believe in God and the Bible. Besides, atheism does not have a good history or at least atheists do not have a good history. Stalin, for example, did far more evil than any Christian ever did.
So it really shouldn't be too hard to understand why Christianity is in the mainstream of society and atheism on the fringe.