By Suzanne McCarroll

DENVER (CBS4)– Airline passengers who say they’ve never had any interest in TSA Pre-check are suddenly flocking to TSA offices to sign up. While they’re hoping to avoid long security lines this summer with pre-check status, they’re also enduring long lines to sign up for the program.

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Karen Fetter has been at the TSA office in Lakewood for more than two hours. She figures she has another hour or so before they call her name to sign her up.

Passengers are paying $85 to qualify for pre-check status. Don Wern showed up early at the TSA office on South Wadsworth but refused to spend his day waiting.

(credit: CBS)

(credit: CBS)

“It just seems the wait is insane. It’s a government operation, what can I tell you?” asked Wern.

At the TSA Enrollment Center at Denver International Airport, appointments are booked out weeks in advance. Walk-ins are accepted but the wait is hours long.

Those who already have TSA Pre-check say it’s worth it.

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“I travel a lot, multiple times a month, I walk up and I get through it,” says one traveler.

But that may be changing.

TSA officials told CBS4’s Suzanne McCarroll that TSA Pre-check lines are getting longer as more people sign up. There can be times when TSA Pre-check isn’t available at all and not all airports offer the separate lanes.

(credit: CBS)

(credit: CBS)

The private service, Clear, is gaining in popularity as a way to avoid lines but it costs nearly twice as much as TSA Pre-check.

“I’ll try anything to get me through faster,” said one traveler signing up for Clear.

TSA officials say if you’re interested in TSA Pre-check it’s best to sign up for an appointment online. McCarroll checked and found the first available appointment is June 24, three weeks from now.

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Suzanne McCarroll is a general assignment reporter at CBS4. Her stories can regularly be seen on CBS4 News at 5 p.m., 6 p.m. and 10 p.m. Connect with her on Facebook and follow her on Twitter @SuzanneCBS4.