The Spencer Davis Group & Millie

His ferocious soul-drenched vocals belying his tender teenage years, Stevie Winwood powered the Spencer Davis Group's three biggest U.S. hits during their brief life span as one of the British Invasion's most convincing R&B-based combos. Guitarist Davis formed the band with Winwood on organ, his brother Muff Winwood on bass, and drummer Peter York. Signing on with producer Chris Blackwell, the quartet got their first hit (the blistering "Keep on Running") from another of Blackwell's acts, West Indian performer Jackie Edwards. After topping the British charts in 1965, the song...