An advocacy group opposing a controversial wind farm in Nantucket Sound -- the backdrop for the first family's vacation next week -- has a message for President Obama. And, if he happens to tune the radio to the local station in Martha's Vineyard, there's a good chance he'll hear it.

The Alliance To Save Nantucket Sound is running the ad in the Vineyard and elsewhere in Cape Cod to coincide with the president's vacation, which starts Sunday. Launched today, the ad will run throughout next week and weekend, said Audra Parker, chief operating officer and executive director of the alliance. The ad buy is a "few thousand dollars," Parker said.

"Mr. President, welcome to the beautiful waters of Cape Cod and the islands," a narrator begins, before making the case against what would be the nation's first offshore wind farm. "National treasures like Nantucket Sound should be off limits to industrial development," he concludes. "Mr. President, please protect our cherished sound."

Click here to listen to the ad, and read more about the controversy here and here.