2000 United States Senate elections

The 2000 United States Senate elections were held on November 7, 2000. The elections coincided with other federal and state elections, including the presidential election which was won by Republican George W. Bush. These elections took place 6 years after Republicans had won a net gain of eight seats in Senate Class 1. Despite George W. Bush's victory in the presidential election, the Republicans lost four senate seats, the most a winning president's party has lost since the passage of the 17th Amendment. This election marked the first election year since 1990 where Democrats made net gains in the Senate. Democrats defeated incumbent Republicans in Delaware, Michigan, Minnesota, Missouri, and Washington, and they won an open Republican-held seat in Florida. In Missouri, the winner was elected posthumously. The Republicans defeated Democratic incumbent Chuck Robb in Virginia, and won an open seat in Nevada. Additionally, Republican Senator Paul Coverdell of Georgia died earlier in the year and was replaced by Democratic appointee Zell Miller, who then went on to win the special election.

These elections resulted in an equal 50–50 split between Republicans and Democrats, with the Vice President casting the tie-breaking votes in the Senate. This was the second tied Senate, after the results in the 1880 elections. Democrats thereby technically won control of the Senate briefly from the Republicans but for only 17 days, since Democrat Al Gore was still Vice President and President of the Senate at the beginning of the new congressional term that started on January 3, 2001, and would remain so until the new Republican Vice President and President of the Senate Dick Cheney would be inaugurated on Inauguration Day on January 20th, 2001, restablishing the Republican majority. However, the Republican majority would only last until June 6, 2001, when Liberal Republican Senator Jim Jeffords of Vermont left the Republican Party and became an independent, deciding to caucus with the Democrats, switching control again to the Democrats. Democrats would lose their majority in the Senate again, being reduced to a plurality, after the death of Democratic Minnesota Senator Paul Wellstone, before Republicans would once more and finally regain the majority in the Senate again after Republican Jim Talent won the 2002 United States Senate special election in Missouri, but since the election was held close to the end of the congressional term, Democrats would technically maintain control of the Senate before the new one started. Republicans were able to firmly establish their majority in the 2002 midterm elections, and Democrats would not regain control of the Senate again until the 2006 midterm elections.

Until 2020, this was the last time that Democrats would win a Senate seat in Georgia. This is the last election cycle with only Republicans and Democrats in the Senate, and the last election cycle in which Republicans won seats in Rhode Island and Vermont.