2016 United States Senate elections

The 2016 United States Senate elections were held on November 8, 2016. The presidential election, House elections, 14 gubernatorial elections, and many state and local elections were held concurrently. In the elections, 34 of the 100 seats—all Class 3 Senate seats—were contested in regular elections; the winners served six-year terms until January 3, 2023. Class 3 had last been up for election in 2010 when Republicans won a net gain of six seats. In 2016, Democrats defended 10 seats, while Republicans defended 24 seats. Republicans, having won a majority of seats in the Senate in 2014, held the Senate majority with 54 seats before this election. Although the Democrats made a net gain of two seats, Republicans retained control of the Senate for the 115th United States Congress. The two Democratic gains came from the defeats of incumbents Kelly Ayotte in New Hampshire and Mark Kirk in Illinois by Maggie Hassan and Tammy Duckworth, respectively. Despite Republicans retaining control of the Senate, 2016 marked the first time since 1986 where Democrats made a net gain of seats in Class 3. This is also the only election cycle since the popular-vote election of senators was mandated by the 17th Amendment in 1913 that the winning party in every Senate election mirrored the winning party for their state in the presidential election. This feat had nearly been accomplished earlier in 1920, which also involved the Class 3 Senate seats, and nearly repeated in 2020; in both cases, every state, with the exception of Kentucky in 1920 and Maine in 2020, voted for the same party in the presidential election and their Senate election. In addition, this election marked the first time since 2000 in which the party in opposition to the elected or reelected presidential candidate made net gains in the Senate; both cases involved the election of a Republican president and the Democrats making gains in the Senate. With the retirement of Harry Reid, Chuck Schumer became the Democratic leader after the elections, while Mitch McConnell retained his position as Senate Majority Leader. As of 2024, this is the last time Republicans won Senate races in Arizona and Georgia, and the last senate election cycle where there were no special elections.