Intelligent people tend to be more religious.
The broad consensus of research shows that people with higher IQs tend to be less religious, not more so.
Is it more logical to be a Christian? Is religion the natural choice of a smart person familiar with more of the evidence? Not according to a broad consensus of studies on IQ and religiosity. These studies have consistently found that the lower the IQ score, the more likely a person is to be religious.
To place these studies in perspective, it is helpful to know the general religious attitudes of Americans today. According to a February 1995 Gallup poll, 96 percent of all Americans believe in God, and 88 percent affirm the importance of religion. However, the degree of religiosity within this group varies considerably. Only 35 percent can be classified as "religious," using a definition that requires them to consider religion important and attend religious services at least once a week. And a March 1994 Gallup poll found that only 20 percent of all Americans belong to that politically active group known as "Christian conservatives."
The following is a review of several studies of IQ and religiosity, paraphrased and summarized from Burnham Beckwith's article, "The Effect of Intelligence on Religious Faith," Free Inquiry, Spring 1986: (1)