Barber took the stage amid cheers and shouts. He promised to support veterans, military families and the middle class. But with Gabby Giffords standing beside him, he also took the opportunity to criticize the vitriol funded by political action committees, particularly super PACs, during the race.
"I say and we say, no to extreme politics. We say yes to working across party lines to secure a strong future for Arizona," Barber said.
Both national Republican and Democrat political action committees spent more than $2 million on this race, mostly in ads attacking the opposing candidate.
Barber, who was seriously injured in the same rampage in which Giffords was shot, beat Republican Jesse Kelly by a seven-point margin. He carried 52 percent of the vote. Kelly called him to concede.
“Alright all, well, this stinks," he told supporters. "So I just called Ron Barber to congratulate him and, statistically, it’s his.”
Kelly narrowly lost a House race to Giffords in 2010.
Both men are already on the ballot for the August primary. They could face off again in the November general election.
Holding onto the seat has been a priority for the Democrats as they seek to regain control of the House in November.
-- The Associated Press contributed to this report.
