By Brad Poole
TUCSON, Ariz., Nov 13 (Reuters) - U.S. Representative Ron Barber, an Arizona Democrat who was an aide to Gabrielle Giffords, faces a recount after his Republican challenger finished the race for a congressional border district with 161 votes ahead of him.
Tea Party favorite Martha McSally claimed a razor-thin victory over Barber, who was struck by gunfire alongside Giffords in the 2011 shooting rampage that killed six people and injured 13 outside a suburban Tucson supermarket.
But Arizona law requires an automatic recount because the final tally in the Second Congressional District left the two candidates separated by less than 0.1 percent of the total, in this case fewer than 200 votes after the Nov. 4 election.
McSally, a retired Air Force colonel and combat pilot who is making her third attempt to capture the House of Representatives seat Giffords vacated in 2012, declared victory on Wednesday night.
"It's time to move from campaigning to governing and working together to bring more opportunity here and move Southern Arizona forward," she said in a statement.
Officials with her campaign did not immediately respond to calls on Thursday, while Barber's spokeswoman Ashley Nash-Hahn said the incumbent has not conceded defeat.
The election now moves to the courts, where the Arizona Secretary of State's Office will ask a judge to order a recount.
It is not clear how long that might take, said Nash-Hahn.
"Instead of declaring victory, we should unite in the commitment to count the votes of Southern Arizonans, and respect the outcome when it is final," she said.
McSally lost in a Republican primary in mid-2012 after Giffords stepped down from what was then District 8. Barber, who was endorsed by Giffords, won a special election and served the remaining few months of Giffords' term.
In the fall of 2012, McSally won the Republican nomination, but then narrowly lost the election to Barber.
The Second Congressional District wraps around the eastern edge of Tucson, a city of about 1 million people that leans Democratic, and it stretches southeast through rural and more conservative Cochise County to New Mexico and the Mexican border. (Reporting by Brad Poole; Editing by Daniel Wallis and Mohammad Zargham)