Kid Rock's influence is everywhere, wedding hip-hop to classic rock and country. Hollywood Undead's slamming “Day of the Dead” imports riff-blazing angst and tough rhymes from Rock's “Cowboy” years, while Brantley Gilbert's Nashville tearjerker “Stone Cold Sober” is slathered in the front-porch realness of Born Free. Uncle Kracker's acoustic-pop ditty “Smile” oozes the feel-good vibes of “All Summer Long.”