As Americans—particularly the political parties—contemplate their demographic future, much of the conversation has centered on questions about what rising Asian and Hispanic populations portend. But there is another important demographic change that could be equally meaningful, but that remains largely ignored: the dramatic reordering of the American religious landscape.

A recent survey conducted by PRRI and the Brookings Institution finds that Millennials (Americans age 18-33) are much more likely than previous generations not only to identify as nonreligious, but to be religious progressives. The survey uses a newly developed religious orientation scale that combines theological, economic and social outlooks to create four categories: religious conservatives, religious moderates, religious progressives, and nonreligious to provide a new look at the American religious landscape.

Among Americans overall, religious conservatives significantly outnumber religious progressives (28% vs. 19%). Another 38% of Americans are religious moderates, while 15% are nonreligious. Religious conservatives make up an even larger share of older Americans. Members of the Silent Generation are much more likely to be religious conservatives than religious progressives (47% vs. 12%) However, among Millennials only 17% are religious conservatives, compared to 23% who are religious progressives.

As both political parties attempt to grapple with the shifting demographic terrain, changes in religious orientation present opportunities and challenges. Younger Democrats maintain a very different religious profile than older Democrats.  The majority of younger Democrats are nonreligious (23%) or religious progressives (31%). In contrast, 6-in-10 (60%) of Democrats who are 65 or older identify as either religious moderates or religious conservatives.

Younger Republicans are also less likely than older Republicans to be religious conservatives. More than two-thirds (68%) of Republicans 65 or older are religious conservatives, compared to less than half (46%) of Republicans under 40. Younger Republicans are twice as likely (15%) to identify as religious progressives or nonreligious than their older counterparts (7%).

As both political parties look to connect with younger voters, a better understanding of the generational changes in religious orientation will almost certainly require adjustments in respective outreach strategies, messaging, and policy platforms.