More than 2.7 million Americans tuned into the sixth-season finale of "Parks and Recreation" that featured a cameo appearance by First Lady Michelle Obama, NBC television said Friday. The sitcom had Obama bumping into its star Amy Poehler at a convention in San Francisco and encouraging her to leave small-town Indiana to take up a National Parks Service job in Chicago, the first lady's hometown. "Change happens, one person at a time," says Obama, following a script that included a plug for her Let's Move initiative to combat obesity among American youngsters. The hour-long episode Thursday also featured music from indie folk band the Decemberists, alt rockers Letter to Cleo and R&B singer Ginuwine, plus a brief appearance by "Mad Men" star Jon Hamm. The first lady, 50, a lawyer by profession, regularly turns up on US television, most recently as a guest on NBC's "The Tonight Show Starring Jimmy Fallon." Previously she's popped up on "Sesame Street" and "The Biggest Loser," among others shows, and she is scheduled to appear -- once again as herself -- on the ABC drama "Nashville" on May 7. NBC has renewed "Parks and Recreation" for a seventh season.