If the presidential race were a contest over who could get their name mentioned the most times in public conversation, Republican candidate Donald Trump would surely be the next occupant of the Oval Office. As of early December, the real estate mogul had spent just over $200,000 on ads – compared to Jeb Bush and his super PAC’s 28.9 million – but continues to enjoy more publicity than anyone else.

This feat was on prominent display late Christmas night, when a married couple noticed a conspicuously positioned Trump ad while driving down 15 Freeway in Corona, California, local news outlets reported Monday.

At first, it felt like a regular evening drive. Nikki Worden and her husband were coming back from the movies, giving a barely glance to the ubiquitous traffic signs overhead and lining the side of the road.

“Ontario Avenue,” said one. “Speed Limit 55,” said another.

But then they noticed something amiss.

On a large electronic sign that would normally announce traffic delays or detours was a message that Worden had never seen before: “Inland Empire supports Donald Trump. Merry Xmas. Vote Donald Trump.”

The couple was so amused by the inexplicable marketing that they exited the freeway, turned around toward the sign and recorded a video which they uploaded to Facebook. In two days, the posting has been viewed 501,288 times and shared by 8,452 users.

“Someone accessed the message sign,” Anne Mayer, a representative from the Riverside County Transportation Commission, told KABC-TV. “Hacked into the message and changed it for their own purposes.”

While officials said enhanced security measures will be enforced, Eyewitness News reporters who went to the scene found the program box unlocked. According to Mayer, making use of an unlocked box still requires a password, which the hacker must have figured out in order to tamper with the program.

The traffic sign was returned to its original, politically neutral state by Saturday.