Democrats made important gains across the states, but the Republicans remain in a strong position.
Going into the 2018 midterm, Republicans had complete control of 26 state governments — meaning that their party held both chambers of the state legislature as well as the governorship. (This count includes Nebraska, which has a nonpartisan, unicameral legislature but is effectively run by the Republicans.) The Democrats, on the other hand, had total control of 8 state governments. Meanwhile, 16 state governments were mixed between the two parties, with one side controlling at least the governorship or one chamber of the legislature.
After the midterms, the Democrats have total control of 14 state governments, compared with 23 for the Republicans. The number of state governments with mixed party control fell to 13. …
… All in all, Tuesday was a good night for Democrats, but the GOP remains in a relatively strong position. It is worth bearing in mind that, prior to the 2010 midterm election, Republicans had total control of just 10 states, compared with 16 states under control of the Democrats; 24 states were split. After the 2010 midterm, Republicans had control of 21 state governments, compared with 11 for the Democrats, and 18 splits. In other words, Republicans will have total control of more state governments in 2019 than they did in 2011.