He is survived by his wife, Adaire McMillan; his sons, Rafe Cannonball McMillan and Ruben McMillan, a sister, Jane Holden McMillan; a brother, Arthur Reese McMillan; and a granddaughter.
Mr. Nixon officially retired from music in 2004, but he “unretired” several times to release and promote compilation albums. He also acted in several major films: He played Jerry Lee Lewis’s drummer, James Van Eaton, in “Great Balls of Fire” and had small roles in “Super Mario Brothers” (1993) and the 1994 film adaptation of the 1960s television show “Car 54, Where Are You?”
Mr. Nixon rarely broke character over his decades of performing, but one incident stood out for his legions of fans.
He was onstage with the Toadliquors at the Hole in the Wall, a venue in Austin, Texas, in 1992, when someone told him that Don Henley of the Eagles, whom he had savagely maligned in one of his more popular songs, was in the crowd.
“I took my guitar off, put it back on, did that like three times,” he told The Austin Statesman in 2014, “then got on the mic and said, ‘Don, do you want to debate? Do you want to fist fight?’”
Instead, Mr. Henley joined him onstage to sing “Don Henley Must Die,” whose lyrics include the lines “You and your kind are killing rock and roll/It’s not because you are O-L-D/It’s ’cause you ain’t got no soul!”
Mr. Henley seemed to know the song by heart, and when they got to the chorus, Mr. Nixon let him take over, singing, “Don Henley must die, don’t let him get back together with Glenn Frey!”
When the song ended, Mr. Henley shook hands with the band and left the bar. Then Mr. Nixon led the Toadliquors in a cover of the Eagles hit “Already Gone.”