Some have pointed to the fact that the North Carolina legislature’s decision in an election contest is “unreviewable” by the courts. Whether or not that is true in North Carolina state courts, the NC legislature through a statute cannot divest the federal courts of jurisdiction to consider U.S. constitutional claims.
If there is clear evidence both that Roy Cooper got more votes in North Carolina, with no plausible basis to claim that fraud infected the result (and by all indications so far, both of these facts are true), it could well be both a Due Process and Equal Protection Clause violation for the North Carolina legislature on a partisan basis to consider a “contest” and overturn the results and hand them to Pat McCrory. There are cases where federal courts have gotten involved in these kinds of ugly election disputes (think Roe v. Alabama, Bush v. Gore). But a brazen power grab without a plausible basis for overturning the results of a democratically conducted election? I expect the federal courts would take a very close look at such a thing.