Though academics have long wondered whether the US will follow the secularizing trend found in most of Europe, the greatest shifts among believers have occurred within Christianity, not away from it.
The three-wave Cooperative Congressional Election Study (CCES)—which surveyed the same individuals in 2010, 2012, and 2014, and started with 9,500 respondents—reveals how few Catholics and Protestants have changed affiliations and how many have moved from one denomination (or nondenomination) to another….
Protestants largely stay Protestant, defecting at similar rates as Catholics during the four-year period: 8.8 percent vs. 9.1 percent. The vast majority of those who leave Protestantism also become nones. Of those who identified as Protestants in 2010, 7.4 percent became nones by 2014, with 5.7 percent identifying as nothing in particular.
The number of Protestants who switched into another religious tradition is minuscule. Out of the sample of more than 4,000 Protestants, just 32 became Catholics, 7 became Buddhists, and less than 5 became Mormons, Jews, Muslims, or Hindus. …
Not only is nondenominational Christianity among the largest affiliations, it also saw the highest rates of defection.
Nondenominational Protestants were more likely than Protestants in other traditions to shift their identity during the four-year period. Around 24 percent of those who claimed a nondenominational affiliation in 2010 switched—about double the volatility among Baptists and Methodists (12% and 12.9% respectively) and nearly three times that of Lutherans and Episcopalians (both at 8.6%) during the same time period.
The major denominational families that had the lowest amount of defections were the traditional mainline traditions, while nondenominational Christianity—almost always considered to be evangelical—had the greatest amount of defections. …The best explanation for this pattern is that a lot of nondenominational Christians seem to know that they are Protestants but are not as knowledgeable about what type of Protestantism to claim. Because of this confusion, many waffle between the most innocuous options on the survey, with “nondenominational” Christian and “none of these” emerging as likely choices. …
Even though many of the largest churches in the US have emerged as nondenominational in affiliation, this tradition has not been able to protect its borders and identity. Fellow political scientist Paul Djupe has written about some of the possible downsides of nondenominational Christianity, including how the movement lacks an organizational structure to act in coordinated ways.
The popularity of nondenominational identity speaks to the declining “brand loyalty” among religious individuals. Though it’s possible that the trend is merely survey error: Individuals select nondenominational Christianity as an easy choice among the options on the list. This may serve as a word of warning to those leading nondenominational churches. While making it easier for individuals to join a nondenominational congregation might lead to dramatic increases in church membership, those weak ties may also lower the barrier for individuals to leave.