(CNN) – Ron Barber became Democratic Rep. Barber of Arizona when he was sworn in Tuesday after winning the special election to fill the seat formerly held by Rep. Gabby Giffords.
Barber, a former Giffords aide, beat Republican Jesse Kelly, an Iraq war veteran, in last week's election and was administered the oath of office by House Speaker John Boehner on the House floor.
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"I am very much looking forward to being able to carry the concerns of the people of Southern Arizona directly to the halls of Congress," Barber said in a statement Tuesday. "I deeply appreciate the trust that the voters of Arizona have placed in me and I will never forget that this seat that I will hold beginning today is not my seat, but the people's seat."
Barber was critically injured during last year's mass shooting that killed six and injured 13 others, including Giffords, who received a gunshot wound to the head. She resigned in January, about one year after the shooting.
Giffords won a close election to a third term over Kelly in 2010 and Barber, who received her endorsement, will serve the remaining six months of that term.