Amy Grant and Vince Gill, “Baby, It’s Cold Outside: It's not so much a matter if this song would appear on this list, but when and by whom. While "Baby, It's Cold Outside.
Colbie Caillat and Brad Paisley, “Merry Christmas Baby: While Colbie Caillat is mostly known for her smart pop songs and easygoing vocal delivery.
Willie Nelson and Kenny Chesney, “Pretty Paper: Although Willie Nelson wrote "Pretty Paper," it was Roy Orbison who first made the song famous with his 1963 hit single.
Blake Shelton and Kelly Clarkson, “There’s a New Kid in Town: Blake Shelton brought a variety-show spirit to his platinum-selling Cheers.