There are 435 House seats. In the outgoing House, the Ds had 235 seats. Currently, in the new House, the Ds lead the Rs, 219 to 205. There are 11 uncalled House races—the Rs lead in 8 and the Ds lead in 3. Those races are not final, but if those numbers hold up, the House will be 222 Ds to 213 Rs. This is a loss of some 13 seats for the Ds. (FYI: One House race in Louisiana is uncalled—but it will go to a run-off between 2 Rs.)
8 governors were up for re-election. In 7 of the 8 races, the incumbent won re-election or if the incumbent was not running, the incumbent’s party won. The exception was Montana, which flipped from D to R. Given that both houses of the legislature were and remain R, the state is now an R-controlled state. Montana has 1 House seat—and it elected an R member.
Both legislative houses of New Hampshire went from D to R. The governor was and remains an R. So NH is now an R-controlled state. New Hampshire has 2 House members, and it elected 2 Ds.
49 states have bicameral legislatures. Minnesota is the only such state where the same party does not control both houses.
Nebraska is the only state which has a unicameral legislature—and its members are technically not partisan.
The Ds had control of 16 states before and after the election.
The Rs had control of 21 states before the election, and 23 states after the election.
After the election, 10 states have divided state control among the two legislative houses and the governor. And Nebraska does not have a partisan legislature.
Seth Barrett Tillman, Not Yet Called Races and State Elections, New Reform Club (Nov. 16, 2020, 12:15 PM), <https://reformclub.blogspot.com/2020/11/not-yet-called-races-and-state-elections.html>;