* Plea could spare Loughner from facing death penalty
* Giffords' husband: Couple satisfied with plea agreement (Updates with guilty plea)
By Tim Gaynor
TUCSON, Ariz., Aug 7 (Reuters) - A college dropout pleaded guilty on Tuesday to killing six people and wounding 13 others, including then-U.S. Representative Gabrielle Giffords, in a shooting rampage in Tucson, Arizona last year.
Jared Loughner, 23, pleaded guilty to 19 criminal counts, including murder. He entered his guilty pleas in federal court in Tucson shortly after he was ruled mentally competent to stand trial by U.S. District Judge Larry Burns.
Under a plea agreement, federal prosecutors, who originally charged Loughner with 49 criminal counts, have agreed not to seek the death penalty against him.
"I plead guilty," Loughner, dressed in a khaki prison jumpsuit, said to each of the 19 counts read in court by Burns.
The 19 counts include murder, attempted murder and the attempted assassination of Giffords.
Giffords, an Arizona Democrat who was seen as a rising star in the party, was meeting constituents at a Tucson supermarket in January 2011 when she was shot through the head at close range. The six people killed include a federal judge and a 9-year-old girl.
Mark Kelly, Giffords' husband, said in a statement released before the hearing that the couple had been in touch with federal prosecutors and were "satisfied" with the plea agreement.
"The pain and loss caused by the events of January 8, 2011 are incalculable. Avoiding a trial will allow us - and we hope the whole southern Arizona community - to continue with our recovery and move forward with our lives," Kelly said.
Giffords resigned from Congress in January to focus on her recovery. Her former aide, Ron Barber, who was also wounded in the shooting spree, won a special election to fill her seat in June and will face re-election in November to serve a full two-year term.
Barber was in court for the hearing but Giffords did not attend.
Loughner was determined unfit to stand trial in May 2011 after he disrupted court proceedings and was dragged out of the courtroom. Court-appointed experts said he suffered from schizophrenia, disordered thinking and delusions.
He has since been held at a U.S. Bureau of Prisons psychiatric hospital in Springfield, Missouri, where he has been forcibly medicated to treat psychosis and restore his fitness to face proceedings in his prosecution. (Additional reporting by Jazmine Woodberry, Alex Dobuzinskis and Steve Gorman; Writing by Dan Whitcomb; Editing by Cynthia Johnston and David Brunnstrom)