NYT:

Mr. Riggleman, as well as outside observers, denounced the setup — enabled by state laws that allow local party officials to choose congressional nominees by conventions instead of traditional primary elections — which has tended to benefit hard-line candidates. As of Sunday morning, Mr. Riggleman had not conceded.

“Voter fraud has been a hallmark of this nomination process and I will not stand for it,” Mr. Riggleman wrote on Twitter late Saturday night. The Virginia Republican Party, he continued, “needs to reevaluate their priorities. We are evaluating all our options at this time.”

Mr. Riggleman’s campaign had objected to the inclusion of a trove of votes from a specific county delegation, raising concerns about whether a handful of ballots had been cast by eligible delegates. The objections were overruled by the committee overseeing the convention.