"Supergirl" doesn't have access to the main characters that are being used in the movies (Clark Kent, Lois Lane, Perry White). So they're tapping into peripheral characters that most folks aren't too familiar with (other than Jimmy, of course).
The brunette next to James/Jimmy is Lucy Lane. The blonde facing them is Kara (Supergirl) Danvers.

Got it. This is not my century....
Golly
Thanks for the post - but she needs a bra like the one Cloris Leachman wore in Young Frankenstein - then she would be awesome....