Gary McKinney can spot the powder blue pickup pulling the gray Airstream travel trailer in any crowded parking lot. It's easy thanks to the map decal of Route 66 that adorns the truck from bumper to bumper.

It shows where the historic highway starts, Chicago. Its red dotted line connects stops along the way in Illinois, Missouri, Kansas and Oklahoma. Shamrock's Conoco Tower Station and U-Drop Inn Cafe is depicted on the passenger side. Amarillo's iconic Cadillac Ranch is on the driver's side. It leaves Texas, heads toward the truck's bed and notes famous places in New Mexico and Arizona, and winds up near the taillights in California.

But Grant Stevens, one of McKinney's passengers, and his band of road-trippers are hoping to gain more from his half-way-across country adventure than mere nostalgia.

Stevens is the Senior Manager of Marketing Campaigns for the National Trust for Historic Preservation. The Trust is wanting to get Route 66 designated as a National Historic Trail.

According to information passed out Wednesday morning in a parking lot at Sixth Avenue and Tennessee Street, the Trust is collaborating with the Route 66 Road Ahead Partnership and others to gain that title. "This permanent federal designation will not bring any new regulations or restrictions. Instead, it will encourage re-investment, boost local economies and entice the public to hit the road again."

"We are trying to organize support by working with local entities," said Morgan Vickers, an intern in the Trust's Denver field office who picked up the caravan in Oklahoma City and will stay until Albuquerque, N.M.

The National Trust for Historic Preservation is a privately funded nonprofit organization working to save America’s historic places. According to its website, its mission is to "protect significant places representing our diverse cultural experience by taking direct action and inspiring broad public support."

That's what the group was doing Tuesday in Shamrock, Wednesday in Amarillo and today at the Midpoint Cafe from 11 a.m. to 1 p.m. in Adrian.

Legislation to amend "the National Trails System Act to designate a trail of approximately 2,400 miles extending from Chicago, Illinois, to Santa Monica, California, as the Route 66 National Historic Trail," or H.R. 801, has already passed the House. Rep. Mac Thornberry, R-Clarendon, was a co-sponsor of the bill.

According to congress.gov, "The trail shall be administered by the National Park Service in a manner that respects and maintains its idiosyncratic nature."

It now is in the Senate.

"We are hoping to get it signed by the president by the end of 2018," Stevens said.

If not, he said he is worried they would have to start all over with a new Congress.

However, before that happens Stevens, who is from Iowa, and Vickers, a native of North Carolina, have some people to meet. They are joined on the month-long trip by McKinney, who is the driver from Ohio, and David Kafer, the group's photographer who is "heading home" to California.

Stevens said he has enjoyed hearing people's stories about what Route 66 means to them.

"Everybody has a different entry point for Route 66," he said.

Some people are excited about the Mother Road because of the eclectic diners or the architecture; others enjoy the classic cars or the unique infrastructure along the route.

He said one of the charms of Route 66 is the very reason many people would rather travel the interstates.

"You can actually feel the land; the ups and downs and the turns," he said.

Kafer said he has enjoyed "the letting go" of trying to get from Point A to Point B as fast as you can. He added people are "very true" to the essence of Route 66; they are looking more for conversation than efficiency in travel. He said Route 66 is a frame of mind.

He and McKinney are on the trip for the full five weeks; the others come and go. Kafer and McKinney were in Springfield, Mo., doing laundry when they met a woman who convinced them that they needed to go eat at Casper's diner. She recommended the chili; Kafer obliged. Then she said he had to have the burger; he obliged even though he said there was no way "I should have kept eating."

"That was a great day," Kafer said.

The people he has met along the way are "super friendly," he said. "The atmosphere and the hospitality are amazing."