1. 1800

Thomas Jefferson
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Thomas Jefferson won the election of 1800.

As fans of the Broadway musical Hamilton well know, this election went down just as the nation’s first political parties were taking shape. At the time, the electoral college process was far different than it is today. Each elector voted for two candidates; the one with the most votes became president, while the runner-up became vice president. Under this system, Thomas Jefferson and his chosen V.P. pick, Aaron Burr, tied for first place 73-73 due to a communication error among Democratic-Republican electors (or a Burr-led conspiracy, depending on whom you believe). President John Adams, a member of the rival Federalist Party, managed only 65 votes. 

For the first of only two times in history, the election went to the House of Representatives. Alexander Hamilton, the nation’s first treasury secretary, turned the tide by lobbying his fellow Federalists to throw their support to Jefferson. Though Hamilton and Jefferson despised each other, Hamilton considered him a safer choice than Burr, whom he claimed “loves nothing but himself—thinks of nothing but his own aggrandizement.” The Virginian walked into the White House, Burr became vice president (he would kill Hamilton in a duel three years later while still in that office) and the 12th Amendment was added to the Constitution to specify that electors vote separately for the nation’s two highest offices.

READ MORE: Aaron Burr's Political Legacy Died in the Duel with Alexander Hamilton

2. 1824

John Quincy Adams
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John Quincy Adams was the sixth president of the United States.

By this time, the Federalist Party had dissolved, and all four candidates for president were Democratic-Republicans. “Old Hickory” Andrew Jackson, hero of the War of 1812, won the popular vote by fewer than 39,000 ballots, and captured 99 electoral votes; Secretary of State John Quincy Adams took 84 electoral votes, with 41 going to Treasury Secretary William Crawford and 37 to House Speaker Henry Clay. As no candidate earned a majority of electoral votes, the election again went to the House of Representatives. Clay was eliminated from contention (only three candidates could be considered) but still controlled the House. 

After a month of back-room negotiations, Clay’s supporters largely threw their weight behind Adams, enabling him to win the House vote, as states that had cast most of their electoral votes for Jackson (Maryland, Illinois, Louisiana and Kentucky) now turned in favor of Adams. When Adams chose Clay as his secretary of state soon after his inauguration, an enraged Jackson called it a “corrupt bargain.” Quitting his Senate post, he vowed to come back and win in 1828, which he did at the head of a new Democratic Party, toppling Adams (by then leader of the National Republican Party) after only one term.

READ MORE: How Andrew Jackson Rode a Populist Wave into the White House

3. 1860

photographic portrait of Abraham Lincoln
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Abraham Lincoln photographed after his November 1860 election.

The presidential election of 1860 wasn’t just contentious—it tore the nation apart. Abraham Lincoln, the chosen nominee of the fledgling Republican Party and a steadfast opponent of slavery, wasn’t even on the ballot in most Southern states. 

While the Democratic Party went with Lincoln’s Illinois rival, Senator Stephen Douglas, as their candidate, the southern branch of the party defected, choosing sitting Vice President John Breckenridge as its candidate. Sen. John Bell of Tennessee rounded out the race on the ticket of the new Constitutional Union Party. 

Lincoln won only 40 percent of the popular vote but took most of the electoral votes in the North, along with California and Oregon. Breckenridge won the electoral votes in most of the South, along with Maryland and Delaware; Bell won Tennessee, Kentucky and Virginia, while Douglas captured only Missouri, despite finishing second in the popular vote. Just weeks after Lincoln’s victory, South Carolina voted to secede. Six more Southern states followed, forming the Confederate States of America in February 1861, with Jefferson Davis as president.

READ MORE: The Grisly Murder Trial That Helped Raise Abraham Lincoln's National Profile

4. 1876

1876 Election, Tilden v. Hayes
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In the U.S. Presidential election of 1876, Hayes vs. Tilden, the electoral counts from four states were in dispute, creating a stalemate that took weeks to resolve and that has been compared to the 2000 election dispute.

This one was a doozy: Democratic Governor Samuel Tilden of New York won 250,000 more ballots in the popular vote than his Republican opponent, Rutherford B. Hayes, and snagged 19 more electoral votes. But Tilden was still one electoral vote short of the required majority (185), and 20 votes remained uncounted: Florida, Louisiana and South Carolina remained too close to call, as each party accused the other of fraud, while in Oregon an elector was declared illegal and replaced, with controversial results. As the crisis mounted, threats of another civil war loomed. 

In an unprecedented move, Congress established a 15-member commission of senators, congressmen and Supreme Court justices (including seven Republicans, seven Democrats and an independent) to decide the election. After the swing vote turned in Hayes’ favor, he was awarded all 20 electoral votes from the disputed states, giving him the necessary 185. After the Democrats threatened to filibuster and block the official vote counting, the issue was settled in negotiations at D.C.’s Wormley Hotel in February 1877. The Democrats would accept Hayes’ victory provided that Hayes remove all federal troops from the South, among other conditions. The compromise consolidated Democratic control of the region, effectively ending Reconstruction and reversing the gains that African Americans had made during the post-Civil War era.

5. 1912

Theodore Roosevelt
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Theodore Roosevelt giving a campaign speech in the 1912 election.

Recently returned from the 10-month African safari he took after leaving the White House, Theodore Roosevelt found himself drawn back into politics as the 1912 election approached. After his close friend and handpicked successor, William Howard Taft, angered Roosevelt and fellow progressives by siding increasingly with the conservative wing of the Republican Party, Roosevelt challenged Taft in the primaries. Denied the nomination, he bolted with his supporters and formed the Progressive Party. In one particularly shocking moment of this wild campaign season, a fanatic shot Roosevelt in the chest during an event in Wisconsin; the self-proclaimed “Bull Moose” actually finished delivering his speech after taking the bullet. 

In the end, Roosevelt and Taft split the Republican vote, helping the Democrat Woodrow Wilson win the White House despite capturing less than 50 percent majorities in many states. Roosevelt finished second and Taft third—the last time in history that a major party candidate would fail to finish either first or second in a presidential election. In fourth place, Eugene Debs, the Socialist Party candidate, won 6 percent of the popular vote, turning in the best-ever showing for a Socialist candidate in a U.S. general election.

READ MORE: Remembering the 1912 Presidential Election

6. 1948

Dewey Defeats Truman
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The outcome of the 1948 election looked clear: President Harry S. Truman was on his way out. In the midterm elections of 1946, both houses of Congress had gone Republican for the first time in nearly 20 years, and opinion polls showed only 1 in 3 Americans approved of Truman’s leadership. Though Republican challenger Thomas Dewey was a strong candidate, having lost a close race to Franklin D. Roosevelt in 1944, Truman’s biggest struggle was opposition within his own party. His own commerce secretary quit to run against him on the Progressive Party ticket, while Truman’s public support of civil rights for African Americans lost him southern, conservative Democrats. These Southern Democrats walked out of the national convention and formed their own States’ Rights Party, known as “Dixiecrats,” behind South Carolina Governor Strom Thurmond. 

Truman campaigned hard throughout the fall, however, making several “whistle stop” train tours across the country in order to make the case that a do-nothing Republican Congress was blocking his proposals and a Republican successor would repeal the New Deal programs that had saved the country from the Depression. Gallup’s last pre-election poll, which showed Dewey beating Truman by five percentage points, went public on Election Day, even though it had been taken in mid-October. After Truman went to bed that night believing he had lost, his Secret Service agents had to wake him at 4 am to break the news of his victory. In a famous photo, a grinning Truman held up a copy of the Chicago Tribune’s morning edition, which went to press earlier than usual due to a printers’ strike. The headline? “Dewey Defeats Truman.”

READ MORE: 'Dewey Defeats Truman': The Election Upset Behind the Photo

7. 2000

WATCH: How the U.S. Supreme Court Decided the Presidential Election of 2000

It was the election that went on forever—or at least that’s what it seemed like. In the race between Al Gore and George W. Bush, it all came down to the outcome in Florida: TV networks initially announced the state had gone in Gore’s favor, then said it was too close to call before finally calling it for the Texas governor. With just a few hundred votes separating the candidates in Florida, the lawsuits and recounts began in full force, including heated disputes over confusing or improperly punched ballots, missing names on voter rolls and multiple requests for ID from minority voters. 

Five agonizing weeks after the election, the U.S. Supreme Court had the final word, ruling by a narrow majority to stop the recount ordered by the Florida Supreme Court on the grounds it violated the constitutional principle that “all votes must be treated equally.” Bush, who won 30 states (counting Florida) and maintained a razor-thin five-vote majority in the electoral college, would be the first candidate in 112 years to win the presidency without prevailing in the popular vote (he trailed Gore by more than 500,000 votes).

READ MORE: How Sandra Day O'Connor's Swing Vote Decided the 2000 Election

8. 2016

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Republican nominee Donald Trump gestures as Democratic nominee Hillary Clinton looks on during the final presidential debate in Las Vegas, Nevada on October 19, 2016.

Bush v. Gore may have been the first time in modern history a president was elected despite losing the popular vote, but it wasn't the last. In 2016, businessman and reality TV host Donald Trump defeated former first lady, senator and secretary of state Hillary Rodham Clinton, even though she received three million more votes than him in the popular vote. The election was unprecedented in many other ways. Trump, who ran despite never having held elected office, brought unabashed populism to the campaign trail. 

Trump made frequent headlines with his statements on immigration—he called for a "total and complete" ban on Muslims entering the United States. In June 2015, he said that when Mexico "sends its people, they're not sending their best. They’re not sending you. They’re sending people that have lots of problems, and they’re bringing those problems with us. They’re bringing drugs. They’re bringing crime. They’re rapists." 

In October 2016, after Trump had accepted the Republican nomination, an audio recording from 2005 surfaced of him bragging about sexually assaulting women. Republican officials condemned the comments but did not renounce their support for Trump.

Despite trailing Clinton in national polls, Trump won several critical states in the Midwest and Rust Belt, giving him an advantage in the Electoral College. He was inaugurated on January 20, 2017. The day after, upwards of five million people around the country protested his new administration at the Women's March