John Gerstner in his church history series on the Ligonier site guesstimates that only 2% are classically Calvinistical when it comes to predestination and election. I think that might be about right. A case could be made for even less.
How is this to be accounted for? Aside from the explanation that so few believe it because it is plainly untrue, there is a sociological explanation, an explanation offered by Stephen Prothero in his book Religious Literacy. He simply blames it on The Second Great Awakening of the early 1800s.
The Second Great Awakening began on the American frontier where Methodism of a less Calvinistic stripe had its way. Moreover, it was a more egalitarian phenomenon, taking place as it did in Jacksonian America, with a bent away from the more elitist, thoughtful and scholarly ways on New England, where the First Great Awakening occurred. Revivalism was born and was soon adopted as a way of reaching both nonChristians and the slothful in church.
This new revivalism led to phenomenal growth in church membership, but it was growth of another kind. The Second Great Awakening was nondenominational in its spirit. During this time we have the birth of nondenominational voluntary organizations, which emphasized cooperation across denominational divides and encouraged different church groups to see each other less as rivals and more as allies. Examples are the American Anti-Slavery Society, the American Temperance Society, the American Bible Society, the American Tract Society, the American Sunday School Union, the American Home Missionary Society, and so on. That which divided Christians was downplayed.
Prothero makes the point that this growth came at a cost, and the cost was religious literacy. The Puritanism of the First Great Awakening went to great lengths to spread religious literacy. And while the evangelicalism of the Second Great Awakening promulgated Bible knowledge, it discouraged theological accuracy as a divisive thing that would check the spread of experiential Christianity. Of course, the rise of Protestant liberalism during this period could only help this slide away from theological precision.
This spirit of nonsectarianism became critical to the burgeoning public school movement. Whereas previously education was an instrument for theological learning, now it eschewed denominationalism and diminished as irrelevant those aspects of Christianity which gave rise to varying denominations.
By the time this process had had its way the Christianity of America is characterized by an emphasis on “core” beliefs, beliefs that could be listed on one side of an 8 1/2 x 11 piece of paper. And preaching followed the script. Gone were the sermons that instructed. Inspiration was in and precision was out.
Calvinism cannot prosper in such an atmosphere. The spirit of the age is against it. In spite of the amount of press Time magazine gives to the New Calvinism, it hardly shows up on the radar screen. To sustain consistent Calvinistical thought requires attention and instruction which must go far beyond the usual diet and appetite of American Christians. Indeed, in some circles we are taught that such a thing is bad and indicates a head religion rather than a true heart religion. The times have to really change for there to be any headway.