Sticker Mule, a printing company known for novelty T-shirts and coasters, was not, until recently, a political animal.

But at an event on Monday night in Amsterdam, N.Y., three hours north of Manhattan, the business took a very public stance in the presidential election, unveiling a glowing, 100-foot-wide endorsement above its headquarters.

“VOTE FOR TRUMP,” the sign read in 12-foot-tall letters, visible from miles away. The company went ahead with a lighting ceremony despite concerns from City Hall that the sign might distract passing motorists and pushback from critics who were baffled at the strident political stand of a printing company in a town of 18,000 residents.

It was worth the trouble, said Anthony Constantino, Sticker Mule’s chief executive.

“I’m here doing this on behalf of all Americans, Democrats and Republicans alike,” Mr. Constantino, 41, said at the event, flanked by mixed-martial artists and a pair of tangerine Tesla Cybertrucks. This was about celebrating free speech and togetherness, he said, and Mr. Trump was “the unity candidate.”

If recent polls are any indication, many of Mr. Constantino’s customers are not likely to agree.

It was the latest example of unusually bold politics in the risk-averse business world, at a time when partisan sentiment seems to be seeping into every facet of American life.

Companies have long tried to influence policy behind the scenes and, in recent years, some have been accused of “virtue signaling” for supporting causes like the Black Lives Matter movement.