Atheists a majority
Not a likely proposition in a free society. Communist nations made some major headway in this area but only by banning religious activity for decades and teaching atheism in schools.
Personally I would prefer the majority to be agnostic. I dislike anyone who claims to "know the truth" and in that sense atheists are the same as religionists. No one can really know if there is a god or not and to claim with certainty there isn't is the same in my book as claiming with certainty there is.