Ottis (pronounced AH-tis) Dewey Whitman Jr. was born in Tampa, Fla., on Jan. 23, 1923, and liked to listen to Jimmie Rodgers yodel on the family radio. After leaving high school he worked at a meatpacking plant, where he lost part of a finger in an accident. In 1941 he eloped with Alma Crist, who would help him overcome his severe stutter.

He joined the Navy, where he served in the South Pacific and entertained shipmates by singing, yodeling and playing the guitar, which he had learned to play upside down and left-handed.

After the war he played weekly in a supermarket and was hired to perform on local radio stations. Colonel Tom Parker, who later managed Presley, heard him and helped him get a contract with RCA Victor Records. Mr. Whitman adopted the stage name Slim and began to appear on the radio show “Louisiana Hayride,” whose performers also included Hank Williams, Johnny Cash and Jerry Lee Lewis.

In 1952 he had his first hit song, “Love Song of the Waterfall,” which 25 years later became part of the soundtrack for “Close Encounters of the Third Kind.” He nonetheless kept his day job as a postman. “Indian Love Call,” which later killed fictional Martians, soon followed and also became a hit. Mr. Whitman stopped carrying mail.

In 1954 he recorded “Rose Marie,” which raced to the top of the charts. His long popularity in Britain began when a promoter arranged to have the song broadcast there from a radio station in Luxembourg. Not until 1992 was the song’s long reign at the top of the charts surpassed, by Bryan Adams’s “(Everything I Do) I Do It for You.” In 1956 Mr. Whitman became the first American country artist to play the London Palladium.

His other hits included “Have I Told You Lately That I Love You,” “Red River Valley,” “Danny Boy” and “I’ll Take You Home Again, Kathleen.” He was given a star on the Hollywood Walk of Fame.