With a tiny handful of votes to be counted and races to be certified, House Republicans have won a majority of the national 'popular' vote, outperforming Democrats by ~4.5 million ballots. For reference, 2010, R's won 242 seats (netting 63!) with 51.7% of the national vote. This year, they will barely have a majority, with roughly 50.7% of the total vote. Dem gerrymanders have worked. Not sure if that qualifies as a "threat to democracy," or if that term is reserved for things that upset liberals.