Baucus started the cowboy hat tradition in 2001 and has ridden a horse in every presidential inauguration parade since.

On Monday he was accompanied by newly elected Montana Gov. Steve Bullock (D) and Montana Republican Rep. Steve Daines.

Baucus, in a tan hat and long tan leather coat, strode through the Capitol Rotunda with Daines, wearing a black hat, on their way to their horses for the ride down Pennsylvania Avenue.

Neither Hatch nor Baucus said they coordinated the hat-wearing event.

But Wyden said it was a matter of Westerners banding together. “This was Oregon’s contribution, the Western contribution,” he said.

Jeremy Herb contributed to this story.