A dozen of New Hampshire Democratic Sen. Jeanne Shaheen’s staffers huddled around a loading dock in the basement of the Hart Building, eagerly awaiting a special delivery.

When a U-Haul truck arrived, they began unloading coolers filled with food and drinks, clearing the way for the main event — an 8-foot-tall moose named Marty and a bear named Kodak.

Moving the stuffed animals onto a dolly, they wheeled them to a nearby freight elevator and up to the fifth floor. At one point Alaska Republican Sen. Lisa Murkowski walked past with a small crowd of reporters, seemingly unfazed by a moose on the loose.

It’s a yearly spectacle at the Capitol to kick off the Experience New Hampshire event, which highlights businesses from the Granite State and joins a handful of other long-standing traditions that liven up the Senate’s otherwise humdrum calendar.

But some of those traditions have an uncertain fate as departing members prepare to leave the Hill, with more than 10 percent of the Senate not returning next year. This week marked the 15th time Shaheen has hosted the event — and also her last, since she won’t be seeking reelection.

“It’s been great to see so many of the same people who are willing to come back with their food or beverages … to hear them talk about the difference that it’s made for them and their business,” she said. 

While Shaheen said she is unsure about future moose displays, she said she hopes the habit continues and has floated the idea of hosting to fellow New Hampshire Democratic Sen. Maggie Hassan. Whoever wins this fall’s election to succeed her could also be an option, she said.

“We want to make sure that people on the Hill understand where New Hampshire fits into the country,” Shaheen said.

Once safely in the office on Tuesday, Marty’s antlers were screwed on, and staffers high-fived over another successful pilgrimage. On the wall behind them hung a photo of the day from a previous year. 

“This is a time in the country when people are losing faith in institutions, particularly young people. And so having these kinds of traditions that people can relate to that help humanize what goes on here I think is really important,” Shaheen said. 

Shaheen wasn’t the only departing senator with a last hurrah this week — Louisiana Sen. Bill Cassidy has been celebrating Seersucker Day dating back to his time in the House, with this now being his last after losing his reelection bid in the GOP primary. 

Almost a dozen senators wore the crinkled cotton fabric Thursday, posing for photos with each other and staff members outside the Senate chamber. 

“The younger people love it, and so obviously, I want young folks to be engaged, feeling a part of the process, because it’s ultimately going to be their country,” he said. 

Brought to the Hill by former Mississippi Sen. Trent Lott in the 1990s, the seersucker celebration was revived by Cassidy in 2014 after a brief hiatus, looking back to a time when the breathable attire provided some relief in the sweltering heat of the pre-air-conditioning Capitol. While the suits are popular with members from the Southern states, Northerners like Sen. Susan Collins of Maine have also been regulars.

“Once, we had more people north of the Mason-Dixon line than the South,” Cassidy said. 

Cassidy has kept the tradition alive with a Democratic senator each year — a role now belonging to Georgia Sen. Raphael Warnock — and hopes it will keep going in his absence, pointing to last summer as a highlight. 

“There were so many people, so many younger people, it was just spilling out. You couldn’t fit them in the photograph,” he said. 

Warnock said while he needs to find a new Republican counterpart for the annual event, it’s not clear who that will be. 

“Let’s see who shows up today,” he said, while waiting for his colleagues to arrive for their annual photo. 

Another departing member with a signature tradition is North Carolina Republican Sen. Thom Tillis, who hosts a recurring Halloween dog parade. That event is also waiting on a successor, though one front-runner could be GOP Sen. Jim Justice of West Virginia, whose 60-plus-pound English bulldog Babydog has become something of a Senate celebrity. 

Spectacle aside, Warnock said these traditions give lawmakers the chance to come together. 

“If you spend 15 minutes on the ground in Savannah, Georgia … you’ll understand why seersuckers are a good thing. It’s hot, and these fabrics are nice and cool in the summer, and it’s a fun thing to do, and I think we do it in a bipartisan spirit here,” he said. “When you think about all the acrimony and toxicity that happens so often in the halls of Congress, even if in small ways we can find a way to laugh together and engage at the human level, I think it helps.”