I think they are doing it deliberately. I think the monied classes that control Washington *HATE* Trump, and so the order has gone out to their lackeys to give Democrats control so that they can impeach Trump.
Trump is a threat to the big monied interests who control Washington in the same way that Teddy Roosevelt turned out to be a threat against those same Monopolistic Robber Barons.
The Nation is controlled mostly by New York and what those Billionaire Donors want.
Nonsense, no "order" is necessary.
Parties in power nearly always lose lots of seats in their first mid-term election, often losing their majorities, just as Democrats did in 2010.
Trump said it himself: the biggest problem Reps face is complacency, thinking now the hard work is done and we can relax.
Then if we add to complacency intramural squabbling and the Republican defeat in November could be historic.
Of course, we won't let any of that happen, will we?