Dunkin' is launching a week-long promotional campaign from December 29th to January 2nd, offering customers free coffee and other deals to combat the "holiday drag." The promotion includes a giveaway of one million free coffees nationwide on Monday, December 29th, with additional offers like a merchandise sweepstakes on New Year's Eve and a free doughnut with beverage purchase on January 2nd. Dunkin' is utilizing social media, particularly Instagram and TikTok, for real-time announcements and to drive digital engagement.