At least two electronic voting machines in a North Carolina county have been taken out of service after early voters reported that the machines repeatedly registered their Democratic choices as Republican votes in Sen. Kay Hagan's contentious reelection bid.

Both incidents took place last week in separate polling precincts in Guilford County, a heavily Democratic stronghold, according to the Greensboro News-Record:

Percy Bostick, 69, of Greensboro said he tried casting a vote for Democrat Kay Hagan at the Old Guilford County Courthouse, only to have the machine register Republican Thom Tillis as his choice.

"I called one of the poll workers over," Bostick said. "She said do it again. And again, I touched the screen at the proper place for Kay Hagan, and it again reported it for Thom Tillis."

On his fourth attempt, the machine registered the vote for Hagan. Another poll worker decided to cancel the ballot altogether and directed Bostick to an adjacent machine, where he was able to cast his ballot without any issues.

A voter at a Guilford recreation center had the same problem last Wednesday, eventually being moved to a new machine after the first kept changing his Hagan vote to a vote for Tillis.

The election between incumbent Sen. Kay Hagan Republican challenger Thom Tillis is expected to be extremely tight and could have national implications, considering Democrats' tenuous hold on Senate control.

Last year, North Carolina's Republican governor, Pat McCrory, signed a far-reaching election law that limited early voting, ended Election Day voting registrations, and required photo ID at the polls, even though multiple studies have shown election-related identity fraud is virtually nonexistent.

"These and other reforms will strengthen the integrity of North Carolina's election process," McCrory said of his law, which did not address or anticipate potential problems with the voting machines themselves.

[Photo credit: AP Images]