Many Iowans (on the Democratic side) felt the Bern, leading the former Independent-turned-Democrat Senator from Vermont to virtually tie Hillary Clinton in the caucuses there on Monday.

While Sanders’s lefty populism has been the catalyst fueling his surprising rise, I think his support also tell us a lot about the future of secularism and its relationship to US politics. In my opinion, Sanders is also benefiting from a more secular Democratic electorate. His message, in other words, is resonating with the rising secular left that is mostly comprised of young people with no religious affiliation.

The entrance polls confirm that Sanders’s base is among young people. The CNN results show that Sanders’s support was concentrated among those under the age of 40. Indeed, more than 8-in-10 Democrats under 30 claimed to support Sanders.

The poll did not show results by religious affiliation. But as a proxy we can use the American Values Atlas, a project of the Public Religion Research Institute. PRRI’s analysis of Iowa religious demographics show that the fastest growth has been among young secular people. Moreover, secular people are largest religious cohort in the Democratic coalition in the state. Still, Iowa is not a very secular place. The size of its secular population is similar to the U.S. percentage, and the secular proportion of its Democratic coalition is similar to the proportion of the Democratic Party nationally.

The next stage is New Hampshire, which is terrain favorable to Sanders because is his turf (New England) and is above-average in its secular composition. The question is whether Sanders’s secular economic populist message can fare better once it moves away from New Hampshire and into more religious states. A friend once argued that candidates like Howard Dean (also from Vermont) had a problem reaching out to more traditional Democratic (religious) constituencies such as Catholics and African American Protestants. If Bernie, with a largely secular message can give Hillary a run for her money without major religious outreach, goes far in this race he will show that secular politics are possible the Democratic Party, even if he falls short in the end.