The Democratic Party performed strongly in federal elections with incumbent Democrats winning re-election to all five Connecticut seats in the U.S. House of Representatives by more than 10 points, and incumbent U.S. Senator Chris Murphy winning re-election by 20 points. Democrats also performed strongly in the Connecticut General Assembly, gaining 12 seats in the State House of Representatives and five seats in the State Senate. However, this "blue wave" did not transfer to all state elections.[2] Although typically considered a "blue state", no Democrat had won a gubernatorial election in the state by more than five points since 1986. This continued in 2018, with Democratic nominee Ned Lamont only winning the governorship by three points.
Two-term incumbent Democratic Governor Dannel Malloy and Lieutenant Governor Nancy Wyman were eligible for a third term but declined to run for re-election. Democratic nominees Ned Lamont and his running mate Susan Bysiewicz won the election against Republican nominees Bob Stefanowski and Joe Markley.
Two-term incumbent Democratic State Attorney General George Jepsen did not seek re-election. Democratic nominee and state representative William Tong defeated Republican nominee Susan Hatfield.