These days, everyone assumes that this is just a fact of life: Evangelicals are Republicans, and Republicans are evangelicals. The powerful alliance culminated in the 2016 election of Donald Trump, tying the reputation of Christianity in America to the Trump brand—maybe permanently.

It wasn’t always like this. One man—a political operative from Georgia named Ralph Reed—devised a plan to harness the energy of young Christians and turn them into America’s most powerful voting bloc, one church mailing list at a time. Decades later, when Donald Trump came on the political scene, Reed knew he would be big—and convinced his fellow evangelicals that they should give him a shot.

Trump’s election was everything Reed spent his entire career fighting for: a president who was anti–abortion rights, listened to evangelical leaders, and advocated for Christians who felt pushed out of the public square. But Reed’s victory had a cost. Many, many Christians have come to feel that their church cares more about politics than Jesus. They have spoken out. They have grieved. And some of them have left.

This week on The Experiment, we have the first episode in a two-part series: Meet the man who turned a disparate group of evangelicals into America’s most powerful voting bloc and invented the evangelical political brand. Then join us next week for Part 2, when we’ll look at the human cost of political victory—a cost that might ultimately be very high.

Further reading: “A Christian Insurrection”

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This episode was produced by Katherine Wells and Alvin Melathe, with reporting by Emma Green. Editing by Julia Longoria, Tracie Hunte, and Emily Botein. Fact-check by William Brennan. Sound design by David Herman.

Music by Parish Council (“Looking for Tom Putt,” “Leaving the TV on at Night,” “Mopping”), Ob (“Ere”), Keyboard (“Staying In”), R McCarthy (“Big Game”), H Hunt (“Journeys”), and Infinite Bisous (“Brain”); provided by Tasty Morsels. Additional music by Lorne David Roderick Balfe (“Petrify (b)”). Additional audio from Warner Bros. Pictures, Access Hollywood, span.org/video/?162337-1/national-prayer-breakfast">C-SPAN, UCLA’s communications-studies department, and The 700 Club.