CHICAGO (AP) – The big Opt-Out looked like a big bust yesterday as Thanksgiving travellers around the country patiently submitted to full-body scans and pat-down searches rather than create havoc on one of the busiest flying days of the year.

In fact, in some parts of the country, bad weather was shaping up as a bigger threat to travellers' hopes of getting to their destinations on time.

For days, activists had waged a loosely organised campaign on the internet to encourage airline passengers to refuse full-body scans and insist on a pat-down in what was dubbed National Opt-Out Day. But the cascading delays and monumental lines that many feared would result had not materialised.

"It was a day at the beach, a box of chocolates," said Greg Hancock, 61, who breezed through security at the Phoenix airport on the way to a vacation in California. He was sent through a body scanner after a golf ball marker set off the metal detector.

His wife, Marti Hancock, 58, said that ever since she was in the air on September 11, 2001, and feared there was a bomb on her plane, she has been fully supportive of stringent security: "If that's what you have to do to keep us safe, that's what you have to do."

The Transportation Security Administration said few people seemed to be opting out.

Some protesters did show up, including one man seen walking around the Salt Lake City airport in a skimpy, Speedo-style bathing suit, and others carrying signs denouncing the TSA's screening methods as unnecessarily intrusive and embarrassing.

By most accounts, though, the lines moved smoothly, and there was no more or less congestion at major US airports than there was in previous years on the day before Thanksgiving.

"I would go so far as to say that National Opt-Out Day was a big bust," said Genevieve Shaw Brown, a spokeswoman for the travel company Travelocity, which had staff at 12 of the nation's largest airports watching for problems.

Protest organisers – some of whom had no plans themselves to fly yesterday – were not prepared to declare the event a flop, saying the publicity alone cranked up pressure on the White House and the TSA to review their security measures.

"The TSA now talks about re-evaluating everything," said James Babb, an organiser for one of the protest groups, We Won't Fly. "That is a tremendous victory for a grassroots movement."

For days, the X-ray scans that can see through people's clothing and the new pat-downs that include the crotch and chest have created a backlash among politicians, bloggers and others. The security screenings have been lampooned on 'Saturday Night Live' and mocked on T-shirts, bumper stickers and underwear emblazoned 'Don't Touch My Junk', from a line uttered by a defiant traveller in San Diego.

At the Phoenix airport yesterday, husband-and-wife protesters Patricia Stone and John Richards held signs decrying "porno-scans" and drew sidelong glances from some passengers but words of support from others, who told them, "Thank you for being here".

"Just because you buy a plane ticket doesn't mean you have to subject yourself to awful security measures. It's not a waiver of your rights," said Stone, 44. "The TSA is security theatre. They're not protecting us."

At Denver International Airport, Chris Maj, a 31-year-old computer programmer, carried a sign that read, "END THE TSA ASK ME HOW". He and three others handed pocket-size copies of the US Constitution.

"They're touching breasts, they're touching buttocks, all of these places that if you or I were to touch, we'd go to jail," he said.

But many passengers brushed off such concerns.

In Atlanta, 22-year-old Ashley Humphries was given a pat-down search of her chest and crotch by a female screener after bobby pins in her hair set off a metal detector.

"I can see how it would make someone uncomfortable, but I'm not easily offended, so it really didn't bother me as much," said Humphries, who was travelling with her fiance to spend Thanksgiving with family in Tennessee.