Kelly Presnell, Arizona Daily Star, AP
Ron Barber Congressional District 2 candidate speaks to the crowd while waiting for final returns from his race against Martha McSally during the election night gathering for Democrats at the Marriott University Park, Tuesday, Nov. 4, 2014, Tucson, Ariz.

PHOENIX — Trailing his Republican challenger by 161 votes with the election heading to a mandatory recount, Democratic Rep. Ron Barber has turned to county supervisors, the Arizona secretary of state and the federal courts in his effort to get uncounted ballots tallied.

He's been turned away so far, and barring an unlikely reversal in a possible appeal of a judge's order that rejected his efforts, Barber likely will head into a recount this week still trailing his opponent, Martha McSally.

Barber's efforts were needed because none of the eight recounts done in the past 16 years has resulted in a change of that many votes, according to an Associated Press review.

And only one of the elections that went to a recount led to a change in the winner, and the margin in that race started at just 4 votes and ended at 13.

Barring a judge's order, Arizona secretary of state Ken Bennett will certify the elections results on Monday, and because the margin between McSally and Barber is less than .10 percent, he'll ask a judge to order the recall required under Arizona law.

Elections officials in Cochise and Pima counties will then recount all the ballots in the 2nd Congressional District.

The only recount in a statewide general election in recent years was in 2010, when voters rejected Proposition 112. That measure was a constitutional amendment that would have required initiative petitions to be filed six months before an election, instead of four months.

After the canvass, the referendum was failing by 128 votes. After all 1,585,522 ballots were recounted, just 33 votes changed from yes to no, increasing the margin of loss to 194 votes.

Longtime Maricopa County elections director Karen Osborne said it would be extremely surprising for the outcome in the 2nd District race to change.

"We've done a couple of statewide recounts and it came within a gazillionth of the same amount," Osborne said. "I don't see this changing a whit."

That's one of the reasons Barber is pushing so hard to get rejected ballots added to the count. His lawyers asked a federal judge last week to order that 133 rejected provisional ballots be counted, and he has requested that Bennett delay the final canvass or count 147 rejected ballots. But the judge turned away the request on Thanksgiving Day, ruling that any problems with the vote count were "garden variety" and not a statewide problem that merited judicial intervention.

The rejected ballots in the two counties were either early votes where the signature didn't match the one on file with the county recorder or provisional ballots rejected mainly because they were cast at the wrong polling place.

State Sen. John McComish, who initially lost his Republican primary bid for a House seat in 2004 before a recount showed him winning, said recounts matter and can change the outcome.

Recalling the days and weeks following the general election, McComish said he was neck-and-neck with another GOP candidate for the second of two House seats in his southeast Phoenix district. When all ballots were counted, he had lost by three votes, a close enough loss to trigger a recount.

"And I thought at the time, well, it's the same machines, everything they did before, why wouldn't the count be exactly the same?" McComish said last week.

But during the recount, a number of ballots that had not registered a vote in the 20th Legislative District were found to actually have votes. The problem, according to McComish and Osborne, was that people used felt-tip markers and other writing devices which either bled through or didn't register on tabulation machines.

"So they were rejected, but when they looked at it they would say 'OK, they clearly voted for McComish or the other guy, Orlich,'" McComish said. "It was obvious that they voted for one or the other so we'll count it. And that was pretty much the difference."

McComish ended up winning the primary by 13 votes and going on to serve three terms in the House and two in the Senate.