The Republican challenger has embarked on an extraordinary effort to reverse his election loss that critics say is testing the boundaries of post-election litigation.

North Carolina’s Supreme Court has ruled that tens of thousands of cast ballots challenged by the trailing candidate in November’s election for a seat on the court must remain in the election count.

Democratic Justice Allison Riggs won her November election by 734 votes, but the court put into play enough votes to possibly hand the seat to her Republican challenger.