Billie Dawn is apt to endure as the theater's best Dumb Broad. Garson Kanin did it in spite of her Brooklyn accent.

"Born Yesterday" begins and ends in the comfortable Washington apartment of Harry Brock, junk-dealer grown plump through sleight-of-hand in the war surplus bonanza. Against a backdrop of dignitaries come to sell their souls for a cut in Harry's ill-gotten gains, Billie--once a chorine in "Anything Goes"--alternately flits and slinks. Her Flatbush lingo leaves the wives of senators non-plussed; journalist Paul Verrill is assigned to "teach her a few things."

Kanin's heroine makes rapid strides toward a whisking acquaintance with basic politics and basic poise. From first-act faux pas (greeting a dowager: "wanna wash yer hands or anything, dearie?") through the rigors of American history and sixth-grade spelling, the Education of Billie Dawn proceeds apace. The instructor is out of the ordinary: a New Republic man, he helps her to discover her social conscience and moral scruples in one fell swoop. Perhaps, she concludes, mistressing is out of date.

Unlike "State of the Union," "Born Yesterday" does not attempt to crackle with timeliness and relevance. The setting is politically topical, but little chance was taken that ideas become so complex as to get in the way, Long and loud, the laughs hinge on modern-day Malapropism and punchy stuff like the often-mouthed "do me a fayvuh, Harry--dwop dead." Judy Holliday's absence from the road company cast is inescapably conspicuous.