The 2022 results ended Democrats’ House majority by a slim margin, while the party retained the Senate. The Republican House majority then struggled to unite behind a speaker, a reminder that a change in party control does not necessarily produce stable leadership.

Midterms often draw less participation than presidential elections, with overall vote totals typically dropping by about a third. Yet the elections determine every seat in the House, one-third of the Senate and many state and local offices. Voters also choose roughly two-thirds of the nation’s governors in midterm years, making the contests consequential well beyond Washington.

The historical record includes several midterms that reordered national politics. In 1930, during the economic crisis that followed the 1929 stock-market crash, Republicans lost 52 House seats and eight Senate seats. Democrats took the House after special elections in 1931, beginning a period of congressional dominance that lasted through World War II.

Republicans made a dramatic return in 1946, capturing both chambers. In 1958, President Dwight Eisenhower’s party fell to 35 Senate seats. The expanded Democratic majority that followed helped create the conditions for later bipartisan votes on major civil-rights legislation, including the Civil Rights Act of 1964 and the Voting Rights Act of 1965.

More recent elections have also reflected voter reaction to the president’s party. Republicans gained 54 House seats and eight Senate seats in 1994, during Bill Clinton’s first term. Democrats took both chambers from President George W. Bush’s party in 2006, amid growing opposition to the Iraq War. In 2010, Republicans made major gains as Barack Obama’s party faced voter discontent over the economy and the Affordable Care Act.

Presidents’ second terms have often been especially difficult for their parties. The 1974 midterms came months after Richard Nixon resigned amid the Watergate scandal, and Republicans lost 48 House seats. In 1986, Democrats gained eight Senate seats, reaching a 55-45 majority and limiting Ronald Reagan’s ability to advance his agenda.

The electoral stakes also reach state capitols. Midterm shifts in state legislatures and governors’ offices can influence policy on issues including voting rules, public services and energy, while serving as an early signal of broader changes in party strength.

The 2026 contest follows the 2024 presidential election and is the decade’s second and final midterm. If it brings a decisive change in congressional control, it would mark a sharper break from 2022 and join a long history of midterms that have altered the balance of power between the White House, Congress and the states.