Tarr, Judith. "Them Old Hyannis Blues"
What if: Numerous musicians were instead politicians, and some politicians were instead musicians.
Summary: After switching from big band to rock 'n roll, the Kennedy bros. play at President Presley's first inaugural ball, and foil an assassination attempt.
Published: In Alternate Kennedys (ed. Mike Resnick), q.v.; and Visions of Wonder: The Science Fiction Research Association Anthology (eds. David G. Hartwell and Milton T. Wolf), Tor 1996 (0312862445BUY, 0312852878BUY).

Tarr, Judith. "Elvis Invictus"
Summary: An overview of Presley's first term, a girl's visit years later to meet the King, and a much later leadership change in the Church of Elvis.
Published: In By Any Other Fame (eds. Mike Resnick and Martin H. Greenberg), q.v.