NIAGARA FALLS -- Some 42 years ago, a Memphis bar band happened upon a young white kid who, somehow, sang like an old blues singer. They hired him. Within a few months, the band had a massive hit, in the form of “The Letter,” a soulful pop song that would eventually be covered to stunning effect by Joe Cocker, but in the meantime was content to become a Top 40 hit for the Boxtops.