I heard she sang over a track pre-recorded by Broderick Crawford.
....after having taken dance lessons from Joan Crawford.
Somewhere between Elaine Stritch and Bette Davis, the vocal stylings of Lauren Bacall.
I think she borrowed the actual vocal chords of Bette, just to misuse them to "sing" this number. She DOES sound a lot like Bette singing "Whatever Happened to Baby Jane". Still, Bacall has a wonderfully slim figure here and is a trememdous stage presence. Just cut back on the cancer-sticks and rest that voice, Lauren !!
There will never be another! Jx