5 Midterm Elections That Changed America

The 1866 midterm elections came at a particularly fraught moment in U.S. history. The Civil War had ended the previous year, and President Abraham Lincoln had been assassinated just days after Robert E. Lee surrendered at Appomattox. That left Andrew Johnson, Lincoln’s vice president, in charge of a federal government divided over how to handle Reconstruction in the South. 

“After the Civil War, there are some huge questions,” says Busch, author of Horses in Midstream: U.S. Midterm Elections and Their Consequences, 1894-1998. “What are we going to do with the Southern states? How committed are we going to be to making political reforms and even constitutional reforms to guarantee the rights of the former slaves? And how much should the federal government be involved in running these states until they're clearly on the right track?” 

Johnson was a Democrat and a Southerner who had remained loyal to the Union during the Civil War. He clashed with Republicans in Congress, particularly Radical Republicans, who pushed for voting rights for Black men. “[T]his is a country for white men, and by God, as long as I am President, it shall be a government for white men,” Johnson declared.  

The 1866 midterms were not only a referendum on Johnson, who had alienated many Republicans, but a test of the country’s commitment to Reconstruction. The results were decisive: Anti-Johnson Republicans won overwhelming majorities in both chambers of Congress, giving them the two-thirds majorities needed to override the president’s vetoes.

Over the next two years, the 14th Amendment was ratified, guaranteeing equal protection under the law, and Congress passed the 15th Amendment, which protected voting rights for all men, regardless of “race, color, or previous condition of servitude.”

"The Radical Republicans in Congress were bolstered tremendously by the midterm election in 1866 and were able to force through what’s sometimes called congressional reconstruction,” says Busch.  

If there’s one rule about midterm elections, it’s that the president’s party almost always gets pummeled. Which is why it’s so significant when the opposite happens. The 1934 midterms—held two years after Democrat Franklin D. Roosevelt was first elected president—were one of those rare exceptions.  

“1934 was remarkable in that Democrats [in both houses of Congress] gained seats,” says Gary Jacobson, a professor emeritus of political science at the University of California, San Diego. “That was the first time in history, and it’s only happened twice since.” 

The 1934 midterms were a referendum on FDR’s handling of the Great Depression, which had left millions of Americans unemployed. Before the 1934 midterms, FDR and Congress had already created several significant New Deal programs, including the Civilian Conservation Corps, which put unemployed young men to work on conservation projects in national forests and parks.  

By 1934, FDR’s own Democratic Party was divided over how much more the federal government should spend on New Deal programs, but the American people spoke loudly at the ballot box. Pro-New Deal Democrats gained nine seats in the House and 10 in the Senate, paving the way for an expansion of the New Deal.

“If you look at some of the most important features of the New Deal—the Social Security Act, the Wagner Act that guaranteed collective bargaining, the biggest of the public works programs like the WPA [Works Progress Administration]—all of those came after the 1934 election,” says Busch. “Not only did the Democrats have bigger margins [in Congress] than they had before, but a real sense of momentum.”  

Four years later, FDR was punished in the 1938 midterms for “overreach” and his attempt to purge his own party of anti-New Deal Democrats. That year, Democrats lost more than 70 seats in the House.  

In the 1964 presidential election, incumbent Democratic President Lyndon B. Johnson cruised to a landslide victory—486 electoral votes to 52—over his conservative Republican opponent, Barry Goldwater. Johnson scored such a lopsided win in part because he was seen as the successor to the martyred John F. Kennedy, who was assassinated less than a year earlier.  

Johnson’s landslide victory also helped Democrats expand their already large congressional majorities. In the Senate, Democrats held 68 of 100 seats, giving Johnson strong congressional support for major Great Society legislation, including the Voting Rights Act of 1965, and initiatives such as the Head Start program.

In the 1966 midterms, however, Johnson and his party suffered a stinging reversal. Republicans gained 47 seats in the House and four seats in the Senate, enough to break the Democratic supermajority. In 23 states, Republican candidates also won their governor’s races, including in California, where the new governor was a former actor named Ronald Reagan. 

The Republican surge in 1966 was fueled in part by the defection of some Southern Democrats to the Republican Party over opposition to Johnson’s civil rights legislation.  

Busch says the 1966 midterm was significant because it signaled a conservative shift in the American electorate that persisted for decades. Republicans won five of the next six presidential elections. One of those winners was Reagan, first elected to office in 1966, but also George H.W. Bush, who was first elected to the House in 1966.   

The 1994 midterm elections marked a major shift in American politics, giving Republicans control of both chambers of Congress for the first time in 40 years.

“1994 was a huge one,” says Jacobson, co-author with Jamie Carson of The Politics of Congressional Elections. “That's when Republicans, who'd been gaining at the presidential level for decades, finally cashed in at the congressional level and became competitive. And Democrats lost their control of the house for the first time in 40 years.”  

There were several reasons for the Republican tidal wave in 1994, which minted 73 new Republican lawmakers in Congress, and flipped both the House and Senate to Republican control. President Bill Clinton’s approval ratings had fallen amid setbacks including his unsuccessful push for health care reform. Clinton also faced conservative opposition to policies including an assault weapons ban and the “Don’t Ask, Don’t Tell” policy which allowed gay, lesbian and bisexual people to serve in the military as long as they did not disclose their sexual orientation. 

Newt Gingrich, a Republican congressman from Georgia, led the charge against Clinton and the Democrats, characterizing them as wasteful, “big government” liberals who were out of touch with the American people. Gingrich helped nationalize the midterms, traditionally dominated by individual congressional races, around a shared Republican playbook called the “Contract with America.”

Another reason for the Republican surge, says Busch, was the decades-long shift of many conservative Southern voters from the Democratic Party to the Republican Party, which accelerated beginning in the 1960s and reached a major milestone in 1994. “1994 was the first time since Reconstruction that the Republicans had a majority of House members from the South.”

The effects of the 1994 midterm elections can still be felt today. Some scholars have identified Gingrich’s confrontational political style and the rise of conservative talk radio, including Rush Limbaugh’s program, as factors that contributed to growing partisan polarization in American politics. Also, midterms have remained highly competitive since 1994, with both houses of Congresses flipping multiple times over the past 30 years.  

The 2010 midterms were another big win for Republicans, but rather than being orchestrated by party leadership, the 2010 “red wave” was fueled by a grassroots conservative movement called the Tea Party.  

The Tea Party rose to prominence in the wake of the Great Recession, fueled by anger over government bailouts of large financial firms. It started as a loosely organized protest movement railing against government spending, the national debt and President Barack Obama’s Affordable Care Act, which opponents dubbed “Obamacare.” As the Tea Party gained steam, top Republicans embraced the group’s anti-establishment message, which translated into big Republican wins in the 2010 midterms.  

Democrats lost 63 seats in the House and six seats in the Senate, making their House losses the party’s largest in a midterm election since 1938. The carnage could have been even worse for Democrats, says Busch. He thinks that in its enthusiasm to shake up the Washington establishment, the Tea Party chose a few too many “outsider” candidates who failed to connect with mainstream Republican voters.  

“I think Republicans could have actually gained control of the Senate in 2010 if there had been more conventional Republican candidates nominated,” says Busch.  

The historic Tea Party victories in 2010 were big news at the time, and Republicans held onto their majority in the House until the 2018 midterms, when the chamber flipped solidly blue. The Tea Party eventually faded as a distinct political movement, but Busch says its anti-establishment politics influenced the Republican Party during Donald Trump’s rise to power.