Kelly, a 6-foot-8 Marine who served in Iraq, has shifted his position on several issues. On his campaign website, he said he would not support any overhaul of Social Security that would privatize it, cut benefits or raise the retirement age. He also has aired a television ad with his grandfather where he promises to protect Social Security and Medicare.
Kelly's campaign declined to make him available for an interview with the AP.
Barber, 66, says that future generations are financing the benefits that older people now receive. Letting workers opt out of the program now would simply lead to the program's collapse.
"Getting people out of the program will not save it," Barber said when the two debated in late May.
Democrats argue that Barber will continue Giffords' work and hope the good will that she engendered with Arizona voters who have following her recovery will benefit him. Before serving as a Giffords aide, Barber worked with the disabled and their families at the Arizona Division of Developmental Disabilities. He and his wife also owned two children's toy and clothing stores.
Jeffrey Rogers, chairman of the Pima County Democratic Party, said he believes voters will be comforted by the mild-mannered, soft-spoken Barber. But Rogers did express surprise that Barber didn't rely on Giffords more for the campaign.
"I would have brought her in more," he said. "She's very popular."
Barber insists that his campaign has reached out to Giffords and "she has done everything we have asked her to do."
After Tuesday's election, the candidates will immediately regroup in an effort to win a full term that would begin with next year's Congress.
Most voters in the current district will become part of the newly redrawn district that becomes more Democratic, with the Republican voter-registration edge dropping from about 25,500 to about 2,000. Independents will continue to play a big factor in determining who represents the region in Congress. Registered independents make up about 31 percent of the voters in the new district.
Freking reported from Washington.
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