Ron Barber, congressman and ex-aide to former U.S. Rep. Gabrielle Giffords (D-Ariz.), is trailing in his House race against Republican Martha McSally.

McSally, a retired Air Force colonel and former combat pilot, maintained a 1,312-vote lead over Barber as of early Wednesday afternoon, the Arizona Secretary of State’s office told Reuters. More than 220,000 votes were cast in the election.

There are still roughly 80,000 ballots outstanding in the race between McSally and Barber, with 40,000 early ballots and 40,000 provisional ballots left to be counted, the Pima County Recorder’s Office told Reuters.

Giffords was seriously wounded when she was shot in the head while holding an event for her constituents in Tucson in an attack that killed six people and wounded 13 others.

Giffords resigned from her House seat in January 2012 so she could focus on her recovery.

Barber, 67, an aide to Giffords at the time, won a special election in June to replace his boss in the House, defeating Iraq War veteran Jesse Kelly.

The congressman, who was favored to win a full two-year term, is in danger of losing his seat.

Barber’s staff was optimistic he could come from behind to retain the House seat.

"The race remains too close to call. Thousands of ballots have yet to be counted, the exact number of which are to be determined," Jessica Floyd, an aide to Barber, said in a statement to Reuters.

Floyd suggested that voting may have been problematic in sections of Pima County but declined to elaborate on any specific issues.

"We will continue to monitor this process and hope to ensure that every person who voted in Southern Arizona has their voice heard," she said.

The McSally camp was eqally optimistic, believing the current results will hold up.

"This is not a traditional ending to our general election, but I guess there's nothing traditional about my life so far, so why start now?" McSally, 46, told a news conference. "We're not surprised that we're in this position ...We've been telling people all along this is going to be a very close race.”