These two midterm elections brought on new eras for politics in the United States

President Grover Cleveland (right) looks down during William McKinley’s presidential inauguration in 1897. Two years earlier, Cleveland’s political party suffered the biggest defeat in U.S. history during the 1894 midterms. (Photo from Library of Congress)

The conventional wisdom is that the Democratic Party has the advantage in the 2026 midterm elections and could become the majority party in one, or both, chambers of Congress. The margin of that anticipated victory is more difficult to predict.

The size of a party’s majority makes a difference. To see why, it’s worth looking back to the second half of the 19th century, when two dramatic midterm election results marked the beginning of important eras in the nation’s history.

1874: A nation changing course

Most American college students, including the ones I taught for more than 40 years, learn that the era of Reconstruction following the Civil War came to an end when the contested presidential election of 1876 led to a deal that combined support for a Republican president with a commitment to withdraw federal troops from Southern states.

The Republican candidate in 1876, Rutherford B. Hayes, did not win the popular vote, but after an Electoral Commission established by Congress resolved disputed electoral college issues, Hayes won a one-vote victory. The White House had a Republican president, but the South was free to block enforcement of the post–Civil War constitutional amendments that protected the civil and voting rights of Black people.

That simple version of the story is not wrong, but it is incomplete. The 1874 midterms set things up for the controversies that would follow.

In the middle of his second presidential term, Republican Ulysses S. Grant was in trouble. There were scandals in Washington and economic hardships from a financial panic in 1873. The Democrats in 1874, amid accusations of fraud and voting irregularities in the South, won over 90 new seats in the House of Representatives and ended the era of Republican dominance on Capitol Hill that began with the election of Abraham Lincoln in 1860.

Before and after the 1874 midterm elections, white Southerners regained control of state governments and used violence and intimidation to suppress Black voter turnout.

Reconstruction was undone by a resurgent Democratic Party that after the 1874 midterms controlled both Southern states and the House. The compromise that removed federal troops from the South and put Hayes in the White House was icing on a cake that was baked in 1874.

1894: The Republican recovery

For two decades following the 1874 midterm elections, America’s two political parties were in constant and close competition for power.

Between the Grant administration and William McKinley’s election in 1896, no president won a majority of the popular vote. Between Grant and McKinley, no president had unified government — a single party in control of the House, the Senate and the White House — for more than two years. Not much got done.

McKinley’s 1896 election was the beginning of a new era of Republican Party dominance in national politics. It would last for decades, and McKinley’s successor, Teddy Roosevelt, would invent the modern presidency, with expanded executive powers and more direct communications with the American people. Political scientists call that kind of change a “realignment,” but it did not begin in 1896. Once again, the previous midterms made a difference.

In the fall of 1894, President Grover Cleveland, the former Democratic governor of New York, was in the middle of his second, nonconsecutive term. It was not going well. Another financial panic, bigger than the one in 1873, accompanied his second inauguration and set in motion a series of economic disasters that produced the largest economic downturn in American history before the Great Depression of the 1930s.

When voters went to the polls in the 1894 midterms, they gave the president’s political party the biggest defeat in U.S. history. Over 100 seats in the House were lost to Republican or third-party candidates. The realignment had begun.

A ‘wake-up call’ election

Huge seat shifts in midterm elections, like those in 1874 and 1894, are extremely rare. Smaller midterm shifts, which occur more often, can be a “wake-up call” that forces a sitting president to recalibrate political strategies.

That’s happened to many modern presidents: Harry Truman in 1946, Dwight Eisenhower in 1958, Lyndon Johnson in 1966, Gerald Ford in 1974, Bill Clinton in 1994, Barack Obama in 2010 and Donald Trump in 2018. Their midterm losses in the House involved 40 or more seats, losses large enough to put the president’s party on notice that something had to change.