"Who's Sorry Now?" is a popular song with music written by Ted Snyder and lyrics by Bert Kalmar and Harry Ruby. It was published in 1923, when Isham Jones took it to number three. "Who's Sorry Now?" was also featured in the Marx Brothers film A Night in Casablanca (1946), directed by Archie Mayo and released by United Artists. Karen Elson with Vince Giordano & The Nighthawks recorded the song for an episode of the HBO television series Boardwalk Empire.

The song was a major hit in 1958 for American singer Connie Francis, who took her cover of the song to number 4 on the Billboard Hot 100 chart and charted at number one in the UK Singles Chart. It spent 22 weeks on the US Billboard Hot 100, her single of greatest longevity, and became her first of eight gold records.

"Who's Sorry Now?" was recorded in 1957 by Connie Francis, and since then the song has become closely identified with her due to the immense popularity of her version which was her breakout hit. Since 1955, Francis had recorded 20 sides for MGM Records and only one ("The Majesty of Love") charted at all. Due to her near-complete failure as a recording artist, MGM informed her that her contract would end after one more disc. With her music career on the line, Francis's father suggested she record "Who's Sorry Now", an old song written back in 1923 by Bert Kalmar and Harry Ruby. He was convinced that it would have crossover appeal with both older listeners and teenagers if the song were given a modernized sound. Francis strongly objected to the idea on the grounds that selling the youth audience on an almost 35-year-old song was "ridiculous", but she finally agreed to it as a favor to her father.

Backed with "You Were Only Fooling (While I Was Falling In Love)", the single was released on October 2, 1957. Initial attention was modest and it looked to be as much of a nonfactor as Francis's previous records, but after Dick Clark's championing of it on American Bandstand in January 1958, the single rose to number 4 on the Billboard Hot 100 that spring, with eventual US sales totaling one million units. In the UK, it was number 1 for six weeks in May and June 1958.

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