Midterm elections, held halfway through a president’s four-year term, can reshape governance by changing which party controls the House and Senate, thereby influencing leadership, committee dynamics, and the feasibility of the president’s legislative agenda.

These results alter prospects for legislation, oversight, and policy direction, with shifts in power affecting governance and potential government action for the remainder of the term.

All 435 seats in the U.S. House are up every two years, while Senate seats are contested roughly one-third of the chamber on staggered cycles; governors and select local offices may also appear on the ballot.

In addition to federal contests, midterms often include gubernatorial and local races, expanding their political impact across multiple levels of government.

Midterm outcomes shape political forecasts and markets, with tools like Kalshi’s American Power Index providing a real-time view of current and anticipated control and risk based on market and non-market inputs.

Importantly, the presidency itself remains off the ballot in midterms, even as party control of Congress is determined.