With his pop-eyed facial expressions and large handlebar moustache, Colonna was known for singing loudly in what Gerald Nachman called a "comic caterwaul", and for his catchphrase, "Who's Yehudi?

Colonna played a range of nitwitted characters, the best-remembered of which was a moronic professor, of which Nachman wrote: Colonna started his career as a trombonist, in orchestras and dance bands in and around his native Boston; he can be heard with Joe Herlihy's Orchestra[1] on discs recorded for Edison Records in the late 1920s.

Fred Allen (then on CBS) gave Colonna periodic guest slots, and, a decade later, he joined the John Scott Trotter band on Bing Crosby's Kraft Music Hall.

In one opera parody, Colonna ‘hollered’ an aria in a “deadpan screech that became his trademark” on Bob Hope's show, Nachman noted.

The others were pianist-comedian Victor Borge and Trotter's drummer, music "depreciationist" Spike Jones; it should be noted, however, that Colonna performed on two songs for the 1938 Warner Bros. film Garden of the Moon, to memorable effect—"Girlfriend of the Whirling Dervish" and "Lady on the Three Cent Stamp", respectively.

In addition to musical numbers, he worked this bit into Road to Rio, along with another of his catchphrases—the film's action periodically cuts to a cavalry riding to the rescue of Bing and Bob, when he exhorts his riders, "Chaaaaaaaaaaaaaaaaaaarge!"

Jack Benny's singing sidekick Dennis Day, a talented impressionist as well as a singer, did an effective imitation of Colonna's manic style and expressions.

(1945), as psychiatrist Dr. Greenglass, and he made a brief appearance with Hope in the "Wife, Husband and Wolf" sketch in Star Spangled Rhythm.

In 1956 he performed the featured song "My Lucky Charm" in the film Meet Me in Las Vegas, starring Dan Dailey and Cyd Charisse.

He provided the voice of the March Hare in the Walt Disney Animated Feature Film Version of Alice in Wonderland (1951) (another radio star, Ed Wynn, voiced the March Hare's companion, the Mad Hatter) and also lent his zany narration style to several Disney shorts, including Casey at the Bat Segment of Make Mine Music (1946) and The Brave Engineer (1950).

His TV work also included voicing Moon Mad Tiger on Time for Beany,[2] serving as the second and last ringmaster/host/performer on Super Circus (1955–56), and appearing in a version of Babes in Toyland on Shirley Temple's Storybook in 1960.

He married Florence Purcell (Porciello), whom he reportedly met on a blind date in 1930; the couple adopted a son, Robert, in 1941.

In the 1944 comedy Trocadero, Johnny Downs, in a vaudeville duo routine, dons a fake Colonna-style moustache and mimics Colonna's singing voice.