(AP) -- An ambulance carried Rep. Gabrielle Giffords along a route lined with well-wishers holding flags Friday, taking the congresswoman to a plane that will fly her to a Houston rehab hospital and her next step in recovery.
It's the first time Giffords left the Tucson hospital since she was brought there with a gunshot wound to the head nearly two weeks ago, and people came to see her off with signs that read "Get well Gabby."
"We want to be here to help her and show her a good farewell, and hope that she has a great recovery," said Al Garcia, a Marine veteran who came on his Harley Davidson motorcycle. "It's through all of these prayers that she's leaving in just two weeks."
Giffords is traveling to Davis-Monthan Air Force Base with an escort from a group of motorcycle riders from a Veterans of Foreign Wars post who know her. From there, she'll be taken by medical flight to a Houston airport, then moved by helicopter to the ICU at Texas Medical Center, where she'll be evaluated before going to the center's rehabilitation hospital, TIRR Memorial Hermann. U.S. Capitol police arrived Thursday afternoon to set up extra security measures at the 119-bed facility.
Giffords husband, Houston-based astronaut Mark Kelly, tweeted Friday: "GG going to next phase of her recover today. Very grateful to the docs and nurses at UMC, Tucson PD, Sheriffs Dept....Back in Tucson ASAP!"
Kelly said he hopes she'll make a full recovery.
A gunman shot Giffords and 18 other people Jan. 8 as she met with constituents outside a grocery store in Tucson. All other survivors have been released from the hospital.
Giffords has been making progress nearly every day in her recovery from a bullet wound to the brain.
Doctors ticked off other markers of her continuing improvement: She scrolled through an iPad, picked out different colored objects and moved her lips. They are unsure whether she is mouthing words, nor do they know how much she is able to see.
"Not everyone always gets 100 percent restoration, but we help them to get to a new normal," said Carl Josehart, chief executive of the rehab hospital that will be the Arizona congresswoman's home for the next month or two.
Dr. Gerard Francisco, the hospital's chief medical officer, will coordinate her care.
"It's going to be a very big team that will address different impairments, but they will have to work together," he said.
First, they'll check her vital signs - make sure her blood pressure and heart rate are good. Then specialists ranging from physical and occupational therapists to speech therapists and psychologists will give a slew of tests to see what she can and cannot do.
The strength of her legs and her ability to stand and walk. The strength of her arms, and whether she can brush her teeth or comb her hair. Whether she can safely swallow on her own. How well she thinks and communicates - not just her ability to speak but also to understand and comprehend, Francisco said.
It's unclear if she is able to speak. And while she is moving both arms and legs, it's uncertain how much strength she has on her right side; the bullet passed through the left side of her brain, which controls the right side of the body.
Giffords will stay at Memorial Hermann until she no longer needs 24-hour medical care - the average is one to two months. Then she can continue getting up to five hours a day of physical and other rehab therapies on an outpatient basis, Josehart said.
"It's hard to speculate on the trajectory or course that any one patient will have," he said.
Despite the steady progress, Giffords has a long road to recovery. Doctors are not sure what, if any, disability she will have.
Sometimes, areas of the brain that seem damaged can recover, said Mark Sherer, a neuropsychologist at the rehab center.
"Some of the tissue is temporarily dysfunctional, so the patient appears very impaired very early on after the injury," but may not be permanently damaged, he said.
A gunman shot Giffords and 18 other people Jan. 8 as she met with constituents outside a grocery store in Tucson. Six people died and the others wounded. All survivors, except Giffords, have been released from hospitals.
The suspect in the attack, Jared Loughner, 22, of Tucson, is being held in federal custody.
"The last 12 days have been extraordinarily difficult for myself, my family, but not only us," Kelly said. "I think it's been very difficult for the city of Tucson, southern Arizona and our country.
Kelly added that Giffords would be proud of the way Tucson has responded. Memorials continued to grow Thursday outside the hospital, in front of her office and at the scene of the shooting.
"I know one of the first things Gabby is going to want to do as soon as she's able to is start writing thank you notes," he said.
Explore further: Doctor: Giffords breathing on her own after attack