We often assume that musicians eat, sleep, and breathe their artistic craft, and while that’s often true, Marty Robbins used music as a means to an end to fund his true dream job: a stock-car racer.

While perhaps best known for his 1959 signature song “El Paso,” Marty Robbins in fact sent 17 singles to the top of the country charts. On this day in 1968, he notched No. 13 with “I Walk Alone.” ...