If there were ever any doubts that Christina should top this list, she set them to rest with her performance of James Brown’s “It’s a Man’s World” at the 2007 Grammy Awards. Even the Godfather of Soul would have been proud. One reason she’s so powerful, Christina sings with her entire body. She feels and enlivens the songs with every fiber of her being. Interestingly enough, she’s the only American in the bunch.
3. JOSS STONE
4. AMY WINEHOUSE [R.I.P.]