Gabrielle Giffords has taken part in a candlelight vigil for the victims of the shooting in which she was badly injured.
The US politician stepped on stage to cheers after being invited to lead the Pledge of Allegiance at a memorial service exactly one year after the shooting in Tucson, Arizona, which left six people dead.
As the crowd chanted "Gabby, Gabby", she limped to the podium, and husband Mark Kelly helped lift her left hand over her heart to make the pledge.
After a year in which she has struggled to speak, Ms Giffords, 41, recited the pledge with the audience, head held high and a smile on her face as she punched each word.
The remembrance service at the University of Arizona ended a day of events, including a church service that drew hundreds of people and a city-wide bell-ringing at 10.11am - the exact time a gunman started shooting outside a Safeway store on January 8, 2011.
With hugs and tears, southern Arizonans remembered the dead, the shattered lives and those who acted heroically after the gunman opened fire at a political meet-and-greet event.
The gunman shot Ms Giffords and then methodically moved down a line of people waiting to talk to her.
Before the vigil, Colorado senator Mark Udall, who was born and raised in Tucson, praised Ms Giffords for working for the good of the country and said other politicians could learn from her and move away from incendiary comments.
"Although Gabby now struggles with her words at times, we know what she's trying to say," Mr Udall said. "It's a simple concept. Words matter, and these days you don't hear our elected officials using words to bring us together. Too often words are used as weapons."
US President Barack Obama telephoned Ms Giffords to offer his support and tell her he and his wife Michelle were keeping her, the families of those killed and the whole Tucson community in their thoughts and prayers, the White House said. He said Ms Giffords was an inspiration to all Americans.