According to the Washington Post's Virginia Politics Blog, the chairman of the Fairfax County Republican Committee issued a memo outlining several "issues that are being looked at" with regard to the Nov 2nd vote count in the 11th Congressional District, including the following:

• In Fairfax County, the voting machines failed to register votes from over 800 ballots, including 106 in the Sideburn precinct alone. (Keith Fimian won that precinct 58% - 40%.) In Prince William County, the machines failed to register votes on more than 200 additional ballots.
• In several precincts, there were actually more votes than voters. That is, voting machines reported a higher number of votes than the number of voters marked on the pollbooks as having voted in the election.
• As of Election Day, there were over 1,150 absentee ballots that had been mailed out to military and other overseas voters but had yet to be received back in the 11th District.
• Officials in Prince William County rejected over 280 absentee ballots, with another 200-300 absentee ballots rejected in Fairfax County.