Beto O’Rourke, the Democratic candidate for U.S. Senate in Texas. Photograph by Sergio Flores / Bloomberg / Getty Images

This week, we inaugurate our new monthly series, The Challengers, which will discuss some of the most contentious midterm races across the country, and examine how revolts against established politicians are reshaping the two parties. On this episode, Lawrence Wright, a New Yorker staff writer and the author of “God Save Texas: A Journey into the Soul of the Lone Star State,” joins Dorothy Wickenden to talk about the political scene in Texas, where Republicans have been in control for more than two decades, and now face insurgent candidates on many fronts.