Measuring (and defining) Evangelicalism (and Fundamentalism)

it should be noted in conclusion that the choice of one’s definitional approach has important consequences with regard to one’s resultant findings. For example, the estimated proportion of evangelical Protestants within American society varies considerably by the approach adopted. Roughly speaking, evangelical Protestants constitute about a quarter of the population when measured in terms of affiliation, about one-seventh when defined in terms of identification, and less than one-tenth of the population when specified in terms of Barna’s list of requirements. Similarly, the political characteristics of those falling within the evangelical Protestant category will vary greatly by the approach adopted. And, because many more African Americans will fall into an evangelical category when based on religious beliefs than when based on denominational affiliation or religious self-identification, the reported proportion of evangelicals voting Democratic in an election is far higher and the group less distinctive (and thus exhibiting lower explanatory power) than what is revealed when evangelicals are defined in terms of self-identification or religious affiliation.