I always thought that it was Liza Minnelli...
Regards,
GtG
I’m pretty sure it was Sophie Tucker because it dates back before Liza began her showbiz career.
About the same time in the 1950’s, Sophie was backstage on the Ed Sullivan show awaiting her cue. The act preceding hers was a troupe of midgets. Suddenly, all the lights went out and there was pandemonium.
Amidst the confusion Sophie was heard to yell, “Somebody get the lights back on! I’m up to my `who’s this?’ in midgets!”