As 23 candidates struggle for attention, one name stands out. Barack Obama is literally more popular than Jesus among Democrats. Unfortunately, neither the former president nor any of the party’s 23 candidates currently seeking the 2020 nomination know quite what to do with that information. Of course, before any serious endorsement conversation can commence, Obama has to finish his book (between rounds of golf and raising millions for his foundation). The writing has been going more slowly than he’d expected, and according to several people who have spoken with him, the 44th president is feeling competitive with his wife, whose...