Giffords attended a concert Saturday night and listened as her husband, astronaut Mark Kelly, spoke on her behalf in praising Barber, who was wounded in the shooting. The couple met Sunday with volunteers to thank them for their work.
"Some of those people used to be her supporters," Kelly said after the meeting. "But now Ron has his own team that's energized to make sure he gets across the finish line on Tuesday, and Gabby is very excited about that."
The Republican candidate, Jesse Kelly — he is not related to Giffords' husband — continued to make the case in the election's final hours that Barber and Obama are out of touch with people in Arizona's 8th Congressional District. Republicans have a 26,000-person edge over Democrats in voter registrations.
"It's time to put a stop to the Barber-Obama team," Kelly's campaign said in its final ad.
Outside groups have spent more than $2 million on the Arizona race. Barber, 66, had a sizable fundraising lead in late May, but spending from conservative groups helped reduce it.
The Arizona 8th is a rare swing district that is competitive virtually every election. Giffords defeated Kelly by about 4,000 votes in 2010 when the election focused on immigration and when tea partiers rallied to the tough-talking former Marine. Now, the economy and jobs are atop voters' concerns.
"Emotions are very high. People are very concerned about the economy and tiring of just limping along," said John Ellinwood, a spokesman for the Kelly campaign.
Kelly, 30, has called for lower taxes and more energy production as a way to improve the economy. He would roll back federal regulations and environmental protections in an effort to boost oil and gas drilling.