By Jazmine Woodberry
TUCSON, Arizona (Reuters) - A Republican challenger had a slight edge over Representative Ron Barber, a former aide to Gabrielle Giffords, in the race for a House of Representatives seat from Arizona, although the election was too close to call early on Wednesday.
Barber, a 66-year-old Democrat who was wounded alongside former congresswoman Giffords in a deadly Tucson shooting last year, had been considered the front-runner in the contest for the newly created 2nd District.
But an unofficial count had Martha McSally, a retired Air Force colonel and former combat pilot, ahead by a slender 1,053 votes with 209 of 216 precincts reporting, the Arizona Secretary of State's office reported. There were 218,660 votes cast.
The Pima County recorder's office said 25,000 early and an unknown number of provisional ballots had yet to be processed.
"While we don't yet know the outcome of this election, I want to say how grateful I am to all those who have stood alongside me - and stood up for what's important to Southern Arizona," Barber said in a statement.
McSally was the first U.S. woman pilot to fly in combat, completing two tours in the Middle East. Her campaign did not immediately respond to a call seeking comment.
She campaigned on a platform of cutting federal regulations, as well as reducing debt and taxes. She also pledged to tighten security on the porous U.S.-Mexico border.
Barber was shot in the face and thigh when a gunman opened fire with a semiautomatic pistol in January 2011 at an event at which Giffords was speaking outside a Tucson-area supermarket. Six people were killed and 13 were wounded.
He ran for office after Giffords stepped down in January to focus on recovery from a head wound. Barber served out the remaining months of her term after winning a special election.
Barber was boosted by an endorsement from Giffords, whose popularity and political stature soared as she battled through a difficult recovery.
Barber focused his campaign on rebuilding the middle class, protecting Medicare and Social Security. He pledged to bolster services for veterans and reforming immigration efforts. He has said he wants more agents at the Arizona-Mexico border.
Giffords, who moved back to her native Arizona earlier this year after undergoing rehabilitation in Houston, turned out with Barber to vote early at a Tucson polling station on Monday.
(Writing by Tim Gaynor; Additional reporting by David Schwartz; Editing by Cynthia Johnston)