Bruno Mars: "It Will Rain"

Who better than Bruno Mars to lead the promotional blitz for Twilight's latest soundtrack? Mars' clean-cut looks and gently scuffed croon make him an ideal nonthreatening crush – and last year's smash "Grenade," on which he threatened to blow himself up for attention, proved his knack for overheated romantic dialogue. Mars gets similarly melodramatic on this ballad ("If you ever leave me, baby, leave some morphine at my door"), but the real point is the song's desperately yearning melody. It sounds a little bit like "Wild Horses," and a lot like Mars' next radio juggernaut.

Listen to "It Will Rain":

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