About this election
The 2020 United States Senate elections, held on 3 November 2020 alongside the presidential vote, produced a 50–50 chamber — the result not finalised until two run-off elections in Georgia on 5 January 2021. Democrats made a net gain of three seats, and with Vice-President Kamala Harris empowered to break ties, the party took control of the Senate for the first time since 2014, giving the incoming Biden administration unified control of government. The split is shown here as Democrats (with their two allied independents) 50, Republicans 50.
Thirty-five seats were on the ballot — the Class 2 senators plus special elections in Arizona and Georgia. Georgia's two races were pivotal: under state law a candidate must win an outright majority, and because neither of its seats was decided in November, both advanced to run-offs in January 2021 that ultimately determined control of the Senate. The map on this page reflects the final outcomes, including those Georgia run-offs.
Democrats flipped four seats. In Colorado, former governor John Hickenlooper unseated Cory Gardner; in Arizona, the astronaut Mark Kelly defeated the appointed incumbent Martha McSally in a special election. Then, in the decisive Georgia run-offs, Jon Ossoff defeated David Perdue and Raphael Warnock defeated Kelly Loeffler, the latter becoming Georgia's first Black senator. Republicans' sole pickup was in Alabama, where Tommy Tuberville ousted Doug Jones, who had won a 2017 special election in unusual circumstances. Several heavily targeted Republican incumbents, including Susan Collins in Maine and Joni Ernst in Iowa, survived despite trailing in pre-election polling.
For two months after election day, control of the Senate hung on Georgia. Enormous national attention and spending poured into the state, and record turnout for a run-off delivered both seats to the Democrats on 5 January 2021 — the day before the certification of the presidential result. Their victories created the 50–50 tie that, with Harris's tie-breaking vote, handed Democrats the majority.
The narrowest possible majority gave Democrats control of the Senate floor and committees but left every senator with an effective veto, forcing the Biden administration to legislate at the pace of its most conservative members. It nonetheless enabled the passage of major spending legislation and the confirmation of President Biden's nominees, including Supreme Court Justice Ketanji Brown Jackson in 2022.
Federal Election Commission (FEC), official 2020 Senate general-election results — fec.gov.
Compiled and reviewed by Bartłomiej Paruzel, Election Data Analyst, from official results. See our data methodology.