It should be easy to gain the minimum 23 seats to put Democrats in charge of the House of Representatives in the upcoming 116th Congress.
The key reality is that there are New York, New Jersey, Pennsylvania, Virginia, Ohio, Illinois, and California seats that seem likely to be switched.
There are suburban districts that traditionally vote Republican, but now are expected to vote Democratic, due to the outrage of women, and the fear that we will have a massive rise in prices due to the crazy tariffs Donald Trump has put upon products from China, as well as the European Union.
in the first midterm after a new President has been inaugurated, invariably the party in control of the White House loses a large number of seats, and often control of Congress.
This was true in 2010, 1946, 1994, 1974, and 1966, years when the party in power lost 63, 55, 54, 48, and 48 seats respectively, as well as losing 6, 12, 8, 4, and 4 seats in the US Senate.
Best bet is that the Democrats will gain 35-40 seats in the House, and have a shot at winning two seats from Republicans, and keeping all of their endangered Senators, particularly now with the Brett Kavanaugh Supreme Court controversy.
With the low public opinion ratings of Donald Trump, history tells us that the average in the first midterm of a new President sees 44 House seats and 5 Senate races lost.
Also, first term midterms, not considering public opinion ratings of the new President, see an average of 29 House and 3 Senate seats lost.
So considering all these factors, it seems that Democratic control of both houses of Congress seems likely in the 116th Congress.