You might recall that one of the items in the budget from the NC legislature put aside $200,000 for investigation of voter fraud. The measure was prompted by the work of the Voter Integrity Project, an outfit that was pushing the idea of widespread fraud to push for voter id and other voter intimidation.
A columnist with the Washington Post did a detailed study and, yes, found voter fraud.
To be specific - 31 cases of voter fraud. Nationwide. Since 2000. Out of one billion votes cast.
Note: these allegations do not include other forms of fraud not prevented by a requirement to show ID at the polls, including absentee ballot fraud, vote buying, vote coercion, fraud in the tallying process, voter registration fraud, double voting, voting by nonresidents, voting by noncitizens, voting by persons disenfranchised by conviction, or fraud in the petitioning process.)