Yes, sheâ€™s had a couple of songs on country radio, and yes, sheâ€™s opening for Kenny Chesney these days. But now we know Kacey Musgraves has arrived: Her voice is on a national commercial for Oreo cookies. Kacey does a version of the Oreo â€œWonderfilledâ€ songin which she wonders what wouldâ€™ve happened had she offered an Oreo to a cute guy she had a crush on in the past. As sheâ€™s singing, stick-figure Oreos act out the lyrics. Itâ€™s super-sweetâ€”like, say, Oreos . . . and Kacey.