TUCSON, Ariz. – In yet another sign of significant recovery during a remarkable week, the gravely wounded U.S. Rep. Gabrielle Giffords was upgraded from critical to serious condition Sunday after a procedure to remove her from a ventilator was successful.

Doctors have been positive, and at times almost giddy, in describing her progress since she was shot point blank in the head Jan. 8.

Giffords responded from the moment she arrived at the emergency room, at first just squeezing a doctor’s hand. Then she raised two fingers. She opened her unbandaged eye shortly after President Obama’s bedside visit Wednesday. Then, more milestones — which doctors said were all indicative of higher cognitive function — were achieved, all with her husband, astronaut Mark Kelly, at her side.

Kelly asked her to give him a thumbs-up if she could hear him. She did more than that. She slowly raised her left arm. By the end of the week, she had moved her legs and arms.

At the hospital, more than 100 people were gathered amid the sea of get-well balloons and cards when the University of Arizona put out a statement upgrading her condition.

“Oh, that’s great news,” said Jean Emrick, a 50-year resident of Tucson, as a violinist played in the background.

Her eyes watering, Emrick said: “Tucson is such a special place and she represents what’s the best of southern Arizona.”

As night fell, candles at the makeshift memorial flickered and a mariachi band played “The Star-Spangled Banner.”

Doctors decided to upgrade her condition because the tracheotomy done a day earlier was uneventful, hospital spokeswoman Katie Riley said. A feeding tube was also put in Saturday, and doctors speculated that they might soon know if she could speak.

Few people survive a bullet to the brain. It is even more rare for people with wounds to the head to regain all of their abilities, and doctors have cautioned that the full extent of Giffords’ recovery remains uncertain.

Giffords and 18 others were shot when a gunman opened fire at a meet-and-greet she was hosting outside a supermarket in her hometown. Six people died, including Giffords’ popular community outreach director, Gabe Zimmerman.

At funeral services for Zimmerman on Sunday, Kelly told the some 700 people gathered that his wife was inspired by Zimmerman’s idealism and warmth, according to the Arizona Republic.

“Gabby and I spoke often about Gabe. She loved him like a younger brother,” Kelly said. “I know someday she’ll get to tell you herself how she felt about Gabe.”