My favorite was Neil Diamond.
I tend to like the "raspy" sort of Jazz sounding male voices . . . I recently went to see Collin Haye in Boston, but I also enjoy Sting, and John Mayer with a shout out to Joey Sumner (he takes after his dad).
So many. Unfair question. If I had to pick a desserted island answer it would be Damien Rice.
John Cougar Mellencamp.
Coldplay
Tim Foust.