It’s the segment that’s surprising: Religiously unaffiliated voters, who may or may not be associated with other civic institutions, seem most excited about supporting or donating to causes, going to rallies, and expressing opinions online, among other activities. Political engagement may be providing these Americans with a new form of identity. And in turn, they may be helping to solidify the new identity of the Democratic Party.

Democrats have traditionally had a strong base of religious voters. A decade ago, more than 80 percent of self-identified Democrats were affiliated with some sort of religion, according to the Pew Research Center. The party was nearly one-quarter Catholic and nearly one-half Protestant, including mainline, evangelical, and historically black denominations. By 2014, those numbers had shifted significantly: Pew found that 28 percent of Democrats identified as religiously unaffiliated.

This year, the God gap also seems to be an enthusiasm gap. In the new PRRI survey of 1,811 respondents, conducted this year in August and September, religiously unaffiliated Democrats were more than twice as likely to have attended a rally within the past 12 months compared with their religious peers. During that time, they were significantly more likely to have contacted an elected official or to have donated to a candidate or cause. And nearly half of religiously unaffiliated Democrats said they had bought or boycotted a product for political reasons or posted political opinions online, compared with roughly one-quarter of their religious peers. “Culturally, this is the subgroup of the Democratic Party that feels most at odds with the direction of the country and what the Trump administration is doing,” said Dan Cox, the research director at PRRI. “These secular Democrats also tend to be the most liberal.”

Secular Democrats were also much more likely to say they’re angry about what’s going on in the country today: Forty-one percent described themselves this way, compared with 28 percent of religious Democrats. Of all the groups highlighted in the data—divided by race, education, geographic region, and more—secular Democrats were the most likely to say they’re feeling this rage. This may shape the political landscape: “There’s no emotion that’s more linked to activism and engagement than anger,” Cox said.

The data on religiously unaffiliated Democrats combines with other statistics to form a rough picture of the voters who have been getting the most civically involved over the past year. Across the board, college graduates were significantly more likely than their nongraduate peers to have signed petitions, volunteered for or donated to a cause, attended rallies, liked a campaign online, called their representative, or changed what they bought for political reasons. Women were also more likely to have done many of these things than men, and they were five percentage points more likely to say they had become more civically engaged over the past two years. In general, Democrats beat out Republicans on a number of measures of civic engagement, especially when it comes to online activism: They were twice as likely to have signed an online petition, encouraged friends or family to get political online, or posted about issues they care about.