North Carolina elections officials as well as local and state prosecutors are investigating allegations of fraud that could involve tampering with or suppressing absentee ballots in a close congressional race there.
The bizarre case could ultimately lead to another election being held for the state's 9th District House seat.
Here's what we know -- and don't know -- about what's happening and where things stand:
The Republican got the most votes
Republican Mark Harris, a Baptist minister, got 905 more votes than Democratic candidate Dan McCready, a businessman and retired Marine, in November's general election.
It came after Harris ousted Republican Rep. Robert Pittenger in the May primary, making Pittenger the first House incumbent ousted in this year's midterm election cycle.
But the North Carolina State Board of Elections and Ethics Enforcement has twice refused to certify Harris as the winner -- making North Carolina's 9th District the only House race in the nation that has not yet been decided.
McCready had initially conceded the race, but withdrew that concession Thursday.
"Over the last week, we have seen the criminal activity come to light, and we have seen that my opponent, Mark Harris, has bankrolled this criminal activity," McCready told North Carolina's WSOC-TV. "And so as of today, I am withdrawing my concession to Mark Harris. And furthermore, I call on Mark Harris to tell the American people exactly what he knew and when he knew it."
Why elections officials won't certify Harris as the winner
The elections board's refusal to certify Harris as the winner stems from its investigation into strange results involving absentee ballots.
The focus of the probe is Bladen County, where veteran operative Leslie McCrae Dowless, a convicted felon who'd been hired by a consulting firm paid by the Harris campaign, led a loosely connected group involved in questionable absentee ballot activity.
North Carolina's State Board of Elections on Friday named Dowless as "a person of interest in connection with an alleged absentee ballot operation in the congressional district."
Investigators are attempting to answer two key questions: Why did Dowless and those connected to him turn in hundreds of absentee ballot requests and sign as "witnesses" on dozens of absentee ballots? And did that group pick up and then destroy hundreds of absentee ballots from areas that would have supported McCready, leading the county to have a much lower rate of absentee ballots being turned in compared with the rest of the district?
Dowless personally turned in 592 of the 1,341 total absentee ballot requests in Bladen County. Only 684 absentee ballots were ultimately cast in the county.
Dowless is also at the center of allegations that absentee ballots were tampered with. A set of 161 ballots obtained by CNN showed that nine people individually signed as "witnesses" on at least 10 absentee ballots. Many of those nine are loosely connected to Dowless, a review of social media accounts and public records showed.
North Carolina requires witnesses to sign absentee ballots. Usually, those witnesses are family members or friends. But a CNN review found three witnesses signed more than 40 ballots each, another signed 30 and three other people signed more than 10 apiece.
One of those people, Ginger Eason, told CNN affiliate WSOC that Dowless paid her between $75 and $100 per week to pick up finished absentee ballots. She said she handed them to Dowless and isn't sure what happened after that.
Who is Leslie McCrae Dowless?
Dowless, 62, is a veteran political operative in Bladen County with a criminal history. He pleaded guilty to felony insurance fraud in 1992.
Campaign finance records show Dowless has been paid more than $23,000 by six campaigns over the last eight years -- and in most of those races, his candidates got a disproportionately large number of absentee votes in his home county.
Harris' campaign paid the GOP consulting firm Red Dome Group more than $400,000 during the 2018 campaign -- and Red Dome Group paid Dowless.
Harris' campaign still owed more than $53,000 after last month's election to Red Dome Group.
More than $34,000 of Harris' debt to Red Dome Group centered on a "reimbursement payment for Bladen absentee" work and other election efforts, according to a post-election report Harris' campaign filed late Thursday with the Federal Election Commission. Red Dome had hired Dowless to perform get-out-the-vote work for Harris' campaign.
Dowless was also paid $940 by the Bladen County GOP this year that they said was for get-out-the-vote efforts.
Dowless has not returned CNN's requests for comment. He has denied any wrongdoing to The Charlotte Observer.
This isn't a new problem for Bladen County
Both Bladen County and Dowless have been at the center of controversy over absentee ballots before.
In 2010, Harold "Butch" Pope, who paid Dowless $6,700, won 81% of the absentee votes cast there in a race for district attorney -- but only 26% of those cast outside Bladen County.
In 2012, state House candidate Ken Waddell, who paid Dowless more than $6,800, won 55% of the absentee vote in Bladen County and just 42% of the absentee vote outside the county.
In 2014, Dowless worked for Jim McVicker, who was narrowly elected sheriff amid allegations of absentee ballot misconduct.
In 2016, Todd Johnson, a Republican who paid Dowless nearly $6,500 as he opposed Rep. Robert Pittenger in a primary, won all but five absentee ballots cast in the district -- even as Johnson finished third in the primary.
This year, Harris won 437 absentee ballots in Bladen County to Pittenger's 17 in the Republican primary, though there was no allegation of ballot tampering in that race at the time. Harris won 420 absentee votes in the general election in Bladen County to McCready's 258.
In a sworn affidavit submitted to the elections board by North Carolina Democrats, one man says he spoke to Dowless in April and that Dowless told him he was working on absentee ballots for Harris and McVicker this year and had more than 80 people working for him.
Wake County District Attorney Lorrin Freeman said her office had launched an investigation into what appear to be voting irregularities in the 2016 election, and expanded the probe to include this year's elections.
Harris' campaign acknowledged it had received a subpoena for documents from the state elections board.
"I want to emphasize -- again -- that the campaign was not aware of any illegal conduct in connection with the 9th District race; however, the campaign intends to cooperate with all lawful investigations of the conduct of the election and, like everyone else, is awaiting the outcome of the investigation by the State Board," said John Branch, an attorney for the Harris campaign, in a statement.
More questionable signatures in Robeson County
A CNN review of absentee ballot envelopes has found irregularities with witness signatures in a second North Carolina county.
Dozens of absentee ballots were witnessed by four people in Robeson County, which is adjacent to Bladen County.
The people who signed multiple ballots are loosely connected to Dowless. One woman signed 57 ballots, nearly 9% of all the absentee ballots that were cast in Robeson County. Another woman, Lisa Britt, who signed 28 of the Robeson ballots, also witnessed 42 ballots in Bladen County. Britt is the daughter of Dowless' ex-wife. Reached by phone, Britt declined to comment.
Unlike in Bladen County, McCready won more of the absentee vote in Robeson County than Harris did.
So what happens next?
The elections board -- a nine-member panel with four Democrats, four Republicans and one nonpartisan member -- is set to meet again on or before December 21. If it determines there's a likelihood the election's outcome was influenced by misconduct, it can order another election.
On Friday, Harris tweeted a video statement in which he said he would support a new election if there is evidence of fraud.
"I'm hopeful that this process will ultimately result in the certification of my election to Congress before the next House session begins," Harris said in the video. "However, if this investigation finds proof of illegal activity on either side to such a level that it could have changed the outcome of the election then I will wholeheartedly support a new election to ensure all voters have confidence in the results."
The state elections board can only order another general election. It cannot undo elections it has already certified -- which means it can't require another primary; it can only order another Harris vs. McCready contest.
The board may also change between now and December 21. A court order had mandated the board return to its previous five-member makeup. Currently, all nine can stay until December 12. It is not known yet if they will get another extension.
The US House has the authority to be the judge of its election returns and members -- which means it could refuse to seat Harris even if the state certifies him as the winner. The House could order its own investigation of the race or reject the returns of the election and order a new one. It's not clear whether that would also mean another primary.