Chaka Khan became eligible for nomination in 2003 and was previously nominated in 2012 and 2016.
Rock & Roll Hall of Fame bio:
"Chaka Khan (born Yvette Stevens in Chicago) came to prominence with the innovative funk/rock group Rufus in the 1970s. At a time when audiences for rock and soul were splitting into different camps, Khan’s voice represented the racial and social integration at the heart of rock and roll.
With her incredible vocal range and mastery of dynamics, Khan has recorded durable and powerful music through four decades. Rufus recorded several excellent albums and had a long run of hits. She broke out on her own in 1978 with Ashford & Simpson’s “I’m Every Woman,” where she successfully mixed rock and disco."