Badger, a 5-year-old Belgian Malinois, was one of four finalists in this year's contest.
Voting was conducted on TSA's social media platforms including Instagram, X (formerly Twitter) and Facebook.
Badger's handler Herb, with whom he's been paired for five years, said he's a fun-loving, hard-working pup who loves salmon bites and chasing his foam ball.
On Monday, TSA announced that Barni of San Francisco International Airport earned the votes for first place.
When Barni is at home with his handler, Michelle Cogel, he loves to play fetch but mainly is obsessed with keeping fit by chasing squirrels, TSA said.
As a reward, Barni will be featured on the front cover of TSA's 2025 Canine Calendar.
The annual contest is held on National Dog Day to acknowledge the hard work canines play at TSA.
Birdie from Milwaukee Mitchell International Airport and Carlo from Kansas City International Airport were also finalists.