On Tuesday, Americans head to the polls in midterm elections midway through the president’s four-year term. Voters will choose all 435 members of the U.S. House of Representatives and 35 of the 100 seats in the U.S. Senate. The vote will determine which party will control parliament for the next two years.
Although the president’s name does not appear on the ballot, the vote is widely seen as a verdict on the presidency, with the president’s party almost always paying the price.
In 18 of the 20 midterm elections held from 1946 to 2022, voters took House seats from the party controlling the White House. The average seat loss was 26 seats. Only the Democrats under Bill Clinton in 1998 and the Republicans under George W. Bush in 2002 bucked this trend.
Political scientists call this the “presidential penalty” or the “intermediate penalty.” As voters use midterm elections to keep the White House in check, the president’s party tends to lose seats simply because it holds power.
House of Representatives: 18 losses in 20 midterm elections
The chart below shows the number of House seats won by the president’s party in each midterm election since 1946, from Harry S. Truman to Joe Biden.
A Democratic president suffered his biggest defeat in a midterm election since 1946. On average, Democrats lost about 29 House seats in midterm elections, compared to about 23 under Republican presidents.
The biggest loss came in 2010, two years after Barack Obama was elected the first African-American president, when Democrats lost 64 House seats and Republicans took control of the chamber. Under Truman, the Democratic Party lost 56 seats in 1946, and under Clinton in 1994, it lost 54 seats, each time losing the House majority.
The worst losses for the Republican Party were in 1958, when Dwight D. Eisenhower lost 50 seats, and in 1974, when Gerald Ford lost 48 seats. In Donald Trump’s first midterm elections in 2018, Republicans lost 42 seats and the House majority.
Big losses often cause the president’s party to lose its majority. The House of Representatives changed hands in seven of the 20 midterm elections since 1946 (1946, 1954, 1994, 2006, 2010, 2018, and 2022).
Senate: 13 losses in 20 midterm elections
The president’s party has lost Senate seats in 13 of 20 midterm elections since 1946, but lost control of the House only six times: in 1946, 1954, 1986, 1994, 2006, and 2014.
Unlike the House of Representatives, where all seats are up for election every two years, senators’ terms are six years and elections are spread out, so only about a third of the 100 seats are contested each cycle. That means which states vote could be as important as the national mood.
Eisenhower’s Republicans lost 13 seats in 1958, their largest loss in the Senate during this period. Truman’s Democrats lost 12 seats in 1946, and Obama’s Democrats lost nine seats in 2014, handing control of the Senate to Republicans.
In some cases, the two rooms may move in opposite directions. In 1982, Ronald Reagan’s Republicans lost 26 House seats but gained one Senate seat. In 2018, Trump’s Republicans lost seats in the House but gained seats in the Senate, and in 2022, Biden’s Democrats lost the House but gained one seat in the Senate.
These divided results indicate that the opposition to the president is not evenly distributed across Congress. A party can lose in a competitive House district and still maintain its position in a favorable Senate map.
What does it mean to lose the House or the Senate?
Losing a seat is not the same as losing control. Lyndon Johnson’s Democratic Party lost 47 House seats in 1966, but maintained its majority. Twenty years later, Republicans under Reagan lost just four House seats, but lost the Senate by eight seats.
Control of the chamber determines who sets the agenda and passes legislation. Bills must pass both houses of Congress before they can be approved or vetoed by the president, so an opposition majority in either chamber could block the president’s plan.
A House majority would allow the party to launch investigations and impeach the president, while a Senate majority would allow the party to veto the president’s nominees, including lifetime federal judgeships.
This year, Democrats need to win three seats in the House and four seats in the Senate. If the Senate is split 50-50, Vice President J.D. Vance could cast the tie-breaking vote, giving Republicans control.
