Claire Davis, a 17-year-old suburban Denver student, has died after being shot in the head by an Arapahoe High School classmate on December 13.
Davis had been critical condition after being shot point-blank in the Colorado school shooting one day before the Sandy Hook (Conn.) massacre anniversary.
Friends and well-wishers had posted prayers online and raised money to help pay for her medical care, but the hospital confirms she has passed away.
"It is with heavy hearts that we share that at 4:29 p.m. this afternoon, Claire Davis passed away, with her family at her side," the hospital said in a statement.
"Despite the best efforts of our physicians and nursing staff, and Claire's fighting spirit, her injuries were too severe and the most advanced medical treatments could not prevent this tragic loss."
"Claire's death is immensely heartbreaking for our community, staff and families."
The school shooting took place just eight miles from Columbine High School.
Karl Pierson, 18, shot Davis, who happened to be sitting nearby with a friend as Pierson, armed with a shotgun and ammunition strapped to his body.
Also carrying Molotov cocktails and a machete, he entered the school and headed toward the library. Davis appeared to be a random target, officials believe.
Pierson likely intended to track down a librarian who had disciplined him, but Robinson said Pierson's arsenal suggested Pierson intended to hurt many others.
Pierson set off one of the incendiary devices and fired five shots before killing himself just one minute and 20 seconds after entering the building.
Students held vigils for Davis after the shooting. Cassmate Maggie Hurlbut said:
"One time I remember I was upset in the hallway, and she came up to me and she just ... it was like, 'Hey Maggie, I know we don't know each other well but are you doing OK?'"
"And I told her yeah, and she was like, 'Anything you need, I'm here for you.'"
"Again, that's who she is, and she just wants to take care of others, and that was really just a good representation of her character and who she was."