# Upset (competition)

An upset occurs in a competition, frequently in electoral politics or sports, when the party popularly expected to win (the "favorite") is defeated by (or, in the case of sports, ties with) an underdog whom the majority expects to lose, defying the conventional wisdom. It is often used in reference to beating the betting odds in sports, or beating the opinion polls in electoral politics.

## Origin

The meaning of the word "upset" has long included "an overthrowing or overturn of ideas, plans, etc." (see OED definition 6b), from which the sports definition almost surely derived. "Upset" also once referred to "a curved part of a bridle-bit, fitting over the tongue of the horse", (now the port of a curb bit), but even though the modern sports meaning of "upset" was first used far more for horse races than for any other competition, there is no evidence of a connection.
In 2002, George Thompson, a lexicographic researcher, used the full-text online search capabilities of The New York Times databases to trace the usage of the verb to upset and the noun upset. The latter was seen in usage as early as 1877.
Thompson's research debunked one popular theory of the term's origin, namely that it was first used after the surprising defeat of the horse Man o' War by the racehorse Upset in 1919 (the loss was the only one in Man o' War's career). The term pre-dates that 1919 Thoroughbred race by at least several decades. In its sports coverage immediately following Upset's victory, the Washington Post wrote, "One might make all sorts of puns about it being an upset." The name of the horse "Upset" came from the "trouble" or "distress" meaning of the word (as shown by the parallelism of the name of Upset's stablemate, Regret).

## Examples of upsets
### Sports

Below is a selection of major upsets from a variety of popular sports around the world. It is not meant to be comprehensive, merely representative.

#### American football

* Heading into the 2007 college football season, the Michigan Wolverines were ranked as the pre-season Number 5 team, and among the favorites for that year's BCS National Championship. As an early season tune-up game, Michigan had booked the lower division Appalachian State Mountaineers for their first game of the season. The Mountaineers surprised the football world by leading 28–17 at the half. Though Michigan clawed their way back to lead 32–31 late into the fourth quarter, the Mountaineers kicked a field goal with 26 seconds left in the game to take the lead 34–32. Michigan managed to use only 20 seconds of game time to drive the ball down to the App State 27-yard line, and as time was expiring the Mountaineers' Corey Lynch blocked a Michigan field goal attempt to secure the upset for App State. The game marked only the second time, to that point, that a lower-division school had beaten a top-division AP-ranked team.
* In Super Bowl III, the senior National Football League was playing their third interleague championship game against the upstart American Football League. The NFL had won the prior two matchups without much difficulty, and it looked poised to do so again, as the Baltimore Colts, with a 13–1 record, behind quarterback Earl Morrall, who led the league in touchdown passes that season and was named NFL Most Valuable Player. The team also had several future Hall of Fame players on the roster, including quarterback Johnny Unitas, relegated to a back-up role following an early-season injury, tight end John Mackey, as well as a defense led by perennial all-pro Bubba Smith. The New York Jets were led by Joe Namath at quarterback, who earlier in the week had "guaranteed" victory against the Colts. Namath's top target, future Hall of Fame wide receiver Don Maynard, was hobbled by an injury, but Namath led the Jets on a run-focused attack that leaned heavily on fullback Matt Snell, who ran for 121 yards and scored the Jets' only touchdown. The Jets defense confounded Morrall, who had only six completions on 17 attempts, with three interceptions in the first half, including an interception to the Jets' Jim Hudson while Colts' star receiver Jimmy Orr, uncovered in the end zone, waved his hands to no avail. Colts' head coach Don Shula put the hobbled Unitas in the game in the second half, and despite a late game touchdown, lost the game 16–7.

#### Association football

* Examples of a "giant-killing" non-league team (Levels 5 to 10) beating a Level 1 opponent in the English FA Cup are National League side Lincoln City's away victory over Premier League side Burnley in the 2016–17 FA Cup and Conference Premier side Luton Town's away victory over the Premier League's Norwich City in the 2012–13 fourth round proper. This was the first defeat of a top flight team by non-league opposition since 1989, when Sutton United claimed a 2–1 victory at home over Coventry City, who had won the FA Cup two seasons earlier and finished that season seventh in the First Division.
* Leicester City F.C., an English football club, were crowned champions of the 2015–16 Premier League. The club had narrowly avoided the relegation the previous season by finishing 14th and being in the bottom of the table the most part of the season. At the beginning of the season, bookmakers had given Leicester City odds of 5000/1 against them winning the league. It was the first English title in their history.
* A major upset in Spanish football was the Alcorconazo, when in the first leg of a 2009–10 Copa del Rey AD Alcorcón won over Real Madrid 4–0. Real Madrid is one of the largest clubs in Spanish football and the world while Alcorcón team played in the third-tier Segunda División B. Because Real Madrid won the second leg only 1–0, Alcorcón advanced victorious to the next round. The half-time substitution of Guti when the score was 3–0 and when he was booked before was another topic in the Spanish press because of words exchanged between the player and his coach, Manuel Pellegrini.

#### Baseball

* The 1906 World Series looked to be one of the most lopsided matchups in World Series history, as the National League powerhouse Chicago Cubs, with a record of 116–36 represented the best winning percentage in modern Major League Baseball history. They faced off against their cross-town rivals, the Chicago White Sox, who finished with the American League pennant having a record of 93–58. The White Sox were dubbed the "hitless wonders" as their .230 team batting average was not only the worst batting average by a team to win their league pennant, it was the worst overall batting average in all of Major League Baseball that season. Buoyed by a pitching staff that held the Cubs to a below .200 batting average for the series, the White Sox showed an uncharacteristic surge of batting prowess in games 5 and 6 with 16 runs on 26 hits over the two games to claim the World Series crown four games to two in what has been called the biggest upset in MLB history.

#### Basketball

* In the 1985 NCAA Division I men's basketball tournament, the Georgetown Hoyas had won the previous national championship, and looked poised to win their second straight, as they entered the 1985 national championship as the defending national champion with the Number 1 overall seed, as well as the Number 1 seed in the East Region, posting a record of 35–2, including a Big East tournament title. Their opponent and Big East rival, the Number 8 seed Villanova Wildcats, entered the national championship with a 24–10 record. Villanova defeated Georgetown, 66–64, in what has been considered one of the biggest upsets in NCAA Division I men's basketball tournament history. As of 2022, this is the only time an 8th-seeded team has won the NCAA tournament and the 1984–85 Villanova team remains the lowest-seeded team to win the NCAA tournament.
* The Stanford Cardinal entered the 1998 NCAA Division I women's basketball tournament with the Number 1 seed in the West Region, posting a record of 21–5, including a Pac-10 regular season title. Their opponent, the Number 16 seed Harvard Crimson, entered the tournament with a 22–4 record and an Ivy League regular season title. Before this match, no Number 1 seed had ever fallen to a Number 16 seed since the field expanded to 64 teams in 1994. Harvard defeated Stanford, 71–67, in what has been considered the biggest upset in NCAA Division I women's basketball tournament history. 20 years later, a Number 16 seed had beaten a Number 1 seed in men's tournament (see below).
* The Virginia Cavaliers entered the 2018 NCAA Division I men's basketball tournament with the Number 1 overall seed, as well as the Number 1 seed in the South Region, posting a record of 31–2, including both an ACC regular season title and ACC tournament title. Their opponent, Number 16 seed UMBC, entered the tournament with a 24–10 record and an America East tournament title. Before this match, no Number 1 seed had ever fallen to a Number 16 seed since the field expanded to 64 teams in 1985. UMBC defeated Virginia, 74–54, in what has been considered the biggest upset in NCAA Tournament history.
* The Purdue Boilermakers entered the 2023 NCAA Division I men's basketball tournament with the Number 1 seed in the East Region, posting a record of 29–5, including both a Big Ten regular season and tournament title. Their opponent, Number 16 seed Fairleigh Dickinson Knights, entered the tournament with a 20–15 record after an 84–61 win over Texas Southern in the First Four. Despite a 67–66 loss in the Northeast Conference tournament championship game to the NEC regular season champion Merrimack Warriors, Fairleigh Dickinson received an automatic bid to the NCAA tournament as the NEC tournament runners-up, while the NEC tournament champion Merrimack was ineligible for the NCAA tournament due to a 4-year transition from Division II. Closed as 23.5-point underdogs, Fairleigh Dickinson shocked Purdue 63–58 to become the second Number 16 seed to beat a Number 1 seed in NCAA Division I men's basketball tournament history.
* Entering the first round of the 2007 NBA Playoffs, the Dallas Mavericks had the best record in all of NBA at 67–15, six games up on second place, while their first round opponent, the Golden State Warriors, had a 42–40 record and had only qualified for the tournament on the last day of the regular season, having needed to win all of their last five games just to qualify. Dallas was captained by power forward Dirk Nowitzki, who was in the midst of a Hall-of-Fame career that would feature 14 all star appearances, and supported by other star players such as Jason Terry, Jerry Stackhouse, Devin Harris, and Josh Howard. Golden State had completely revamped their team mid-season, including two starters (Stephen Jackson and Al Harrington), who arrived in January in a blockbuster 8-player deal with the Indiana Pacers. Baron Davis was the unquestioned star of the playoff run, as he dominated the Mavericks, averaging 25.3 points, 6.5 assists, and 2.9 steals per game, as the Warriors would knock off the Mavericks four games to two.
* Entering the second round of the 2020 NBA Playoffs, The Los Angeles Clippers, under the guidance by championship head coach Doc Rivers, were widely regarded as frontrunners for the championship. Armed with star talents like Kawhi Leonard, who came off a championship win with the Toronto Raptors, and Paul George, a previous MVP candidate and first-team All-Defensive player, and defensive guard Patrick Beverley, the Clippers had high expectations. Their deep bench, featuring Montrezl Harrell and Lou Williams, added to their championship aspirations, while their strong defensive prowess further solidified their position. However, the Denver Nuggets, guided by the dynamic duo of Jamal Murray and Nikola Jokić, emerged as formidable challengers. Murray's explosive scoring prowess, highlighted by a remarkable 40-point performance in Game 7, combined with Jokić's extraordinary playmaking and versatility as a center, were instrumental in fueling the Nuggets' remarkable comeback. This unforeseen development showcased the Nuggets' remarkable resilience and their strategic acumen in exploiting the Clippers' defensive weaknesses. In contrast, the Clippers' star players faltered significantly in the crucial Game 7, with Leonard managing only 14 points and a 6-of-22 shooting performance, and George contributing a mere 10 points at a shooting efficiency of 25%, including a notable miss that hit the side of the backboard during a 3-point attempt. Notably, both stars were unable to score in the 4th quarter. This series of events culminated in a stunning reversal, as the Clippers lost their dominant 3–1 series lead, becoming the 12th team in NBA history to do so. The Nuggets, driven by the exceptional performances of Murray and Jokić, clinched a victory in what became one of the most unexpected and memorable upsets in recent NBA playoff history.
* Entering the first round of the 2023 NBA playoffs, the Milwaukee Bucks earned the inaugural Maurice Podoloff Trophy as the NBA's best regular season team with a 58–24 record, while their first round opponent, the Miami Heat, had a 44–38 record, had won their second straight Southeast Division, had qualified for the playoffs for the fourth straight year, and earned the eighth spot in the Eastern Conference. Despite losing to the Atlanta Hawks 116–105 in the first play-in tournament game, Miami bounced back and defeated the Chicago Bulls 102–91 in the final play-in tournament game. Milwaukee was coached by Mike Budenholzer, who is a two-time NBA Coach of the Year and won the NBA championship in 2021. The Miami Heat knocked off the Milwaukee Bucks in five games, in what has been considered one of the biggest upsets in NBA playoffs history. This made the Heat the first number 8 seed to win a playoff series after qualifying for the play-in tournament. This also made the Bucks the sixth number 1 seed to lose a playoff series in the opening round (the others being the 1994 SuperSonics, 1999 Heat, 2007 Mavericks, 2011 Spurs, and 2012 Bulls).

#### Cricket

* In the 1983 Cricket World Cup, the third edition of the tournament, the West Indies cricket team had won both of the previous two World Cups and looked poised to win their third. Their opponent in the finals, India, had never made it out of the group stage before 1983. India went to bat first, and managed 183 before being dismissed with five overs left. West Indies star batsman, Viv Richards, hit a hook towards the leg-side boundary, where Indian captain Kapil Dev made a running catch to get out the West Indies best batsman. Among the remaining batsman, only Jeff Dujon managed more than 20 runs, and West Indies were bowled out at 140, giving India their first World Cup.

#### Ice hockey

* Entering the medal round of the 1980 Winter Olympics, the Soviet Union had won four consecutive gold medals of the previous four Winter Olympics and were heavily favored to win another gold medal. Their opponent, the United States, consisted entirely of collegiate and amateur players and under head coach Herb Brooks, had finished second in Blue Division behind Sweden (based on goal difference) and qualified for the medal round. The U.S. pulled off a 4–3 upset over the Soviets, in what has since become known as the "Miracle on Ice". After that loss, the Soviets pummeled Sweden to settle for silver, while the U.S. went on to win gold after defeating Finland.
* Entering the first round of the 2019 Stanley Cup playoffs, the Tampa Bay Lightning earned the Presidents' Trophy as the NHL's best regular season team with a 62–16–4 record (128 points), while their first round opponent, the Columbus Blue Jackets, had a 47–31–4 record (98 points), had qualified for the playoffs for the third straight year and earned the second wild card spot in the Eastern Conference. The Blue Jackets swept the Lightning in four games and won the playoff series for the first time in franchise history, in what has been considered the biggest upset in Stanley Cup playoffs history. This marks the first time in Stanley Cup playoffs history that the Presidents' Trophy winners were swept in the opening round.
* Entering the 2023 Stanley Cup playoffs, the Boston Bruins had set new NHL records for single-season wins and points, finishing with a 65–12–5 record (135 points), and earning the President's Trophy. By contrast, their first round opponent, the Florida Panthers, had narrowly qualified for the playoffs, finishing with a 42–32–8 record (92 points), and clinching an Eastern Conference wild card berth one day after their penultimate regular-season game. The Panthers defeated the Bruins in seven games, rallying from a 3–1 series deficit and winning three straight games to eliminate Boston; additionally, the team advanced to the second round of the playoffs for just the third time in franchise history. The 43-point difference between the two teams represented the largest upset by standings position of any best-of-seven playoff series in NHL history.

#### Skiing

* Ester Ledecká won the gold medal in super-G alpine skiing at the 2018 Winter Olympics, after finishing 0.01 seconds ahead of the 2014 Olympics defending gold medalist Anna Veith, who had already been proclaimed the winner by many media outlets. Ledecká was ranked 49th in the event before the Olympics and had never medalled in any World Cup level international skiing event.

#### Quizzing

* At the 4th edition of the Mirko Miočić Memorial in 2020, an unexpected shift occurred in the pairs event of the quizzing world. After years of dominance by Dean Kotiga and Perica Živanović, who had long been the gold standard in competitive quizzing duos, the duo of Mladen Vukorepa and Karlo Plazina stunned everyone with a remarkable upset victory. The event, named in honor of Croatian quiz legend Mirko Miočić, has always been a significant fixture on the quizzing calendar, attracting some of the top quizzing talent in the region. For years, Kotiga and Živanović had made the pairs event their own, consistently emerging victorious and seemingly unbeatable due to their incredible breadth of knowledge and synergy as a team. However, 2020 saw Vukorepa and Plazina rise to the occasion. They capitalized on their own deep knowledge base and effective teamwork, proving that even the strongest champions can be challenged. Their victory not only broke the long-standing dominance of Kotiga and Živanović but also signaled a new era in Croatian and regional quizzing. The duo’s win at the Mirko Miočić Memorial was a testament to their preparation and resilience, cementing their place among the top quizzing pairs. The win was significant not just because of the upset, but because it occurred at such a prestigious event, where the competition is fierce and the pressure high. Vukorepa and Plazina’s triumph will long be remembered as a key moment in the tournament's history and in the wider quizzing community.

#### Boxing

* Mike Tyson vs. Buster Douglas Undisputed heavyweight champion Mike Tyson Lost his belt to Buster Douglas Despite being the 42 to 1 favorite It was the first loss of Tyson's career

### Politics

Below is a list of elections which have extensively been described as upsets by a number of major media sources. It is not meant to be comprehensive, merely representative.

#### Argentina

* 2023 Argentine primary elections: presidential candidate Javier Milei of La Libertad Avanza (LLA) finished as the most voted candidate in the election. Opinion polling for the 2023 Argentine general election had predicted that Sergio Massa of the Union for the Homeland (UP) led by the Justicialist Party (PJ) would be the most voted candidate and Juntos por el Cambio (JxC) the most voted coalition overall. It was the first time that a right wing candidate won the primary elections since the 1916 Argentine general election; since then, all presidents of Argentina were either from the Radical Civic Union (UCR) or derivates, the Justicialists, or JxC.

#### Australia

* 1993 federal election: the ruling 10-year old Labor Party government won a fifth consecutive term in office, despite trailing the opposition Liberal-National Coalition during the election campaign.
* 2015 Queensland state election: Three years after the Queensland Labor Party was turfed out of state government by the Liberal National Party of Queensland (LNP) in a massive landslide and reduced to 7 seats in the 89 seat state parliament, Labor overturned the LNP's massive majority and returned to power on a massive swing, forming a minority government. The LNP lead in the opinion polls and the scale of the LNP victory in the previous election made it appear that its defeat was unlikely.
* 2019 federal election: the ruling Liberal-National Coalition won an absolute majority of 77 out of the 151 seats in the House of Representatives, despite trailing the opposition Labor Party in opinion polls for almost three years.

#### Croatia

* 2016 parliamentary election: The election yielded a surprise victory for the Croatian Democratic Union, though most opinion polls had predicted the People's coalition would have the largest share of seats in Parliament.
* 2020 parliamentary election: The ruling Croatian Democratic Union obtained an upset victory over the Restart Coalition, who had previously been leading in opinion polls for several weeks prior to the election.

#### Czech Republic

* 2013 presidential election: Karel Schwarzenberg finished as the runner-up over former prime Minister Jan Fischer who was previously leading polls. He was ultimately defeated by Miloš Zeman.
* 2021 parliamentary election: Opinion polls had shown ANO 2011 as the clear front-runner while Spolu was polling second. No opinion poll placed SPOLU in the first place and it was widely believed that ANO 2011 would win the election. Eventually Spolu received the higher number of votes and its leader Petr Fiala became the new Prime Minister.

#### Ecuador

* 2023 general election: presidential candidate Daniel Noboa of the National Democratic Action unexpectedly came in second place, advancing to a runoff election against Luisa González of the Citizen Revolution Movement, despite Noboa's poor performance in general polls leading up to the election. Noboa ended up defeating González in the runoff election.

#### France

* 2002 presidential election: far-right candidate Jean-Marie Le Pen, of the National Front, finished as the runner-up over prime minister Lionel Jospin and thus progressed to a run-off against incumbent president Jacques Chirac. Chirac would ultimately defeat Le Pen in a historic landslide.
* 2024 French legislative election: When polls indicated that the National Rally, under Marine Le Pen, would win an outright majority after winning the first round of the election, they were unexpectedly beaten by the New Popular Front, a four-party left-wing alliance.

#### The Gambia

* 2016 presidential election: dictatorial president Yahya Jammeh, in power since 1994, unexpectedly lost the election to opposition candidate Adama Barrow.

#### India

* 2024 Indian general election: The governing Bharatiya Janata Party led by Prime Minister Narendra Modi (in power since 2014) unexpectedly lost its majority in the Lok Sabha, despite opinion polls predicting them expanding their majority. Its alliance, the NDA, did win a majority of seats, requiring a coalition government.

#### Israel

* 1996 Prime ministerial election: Although Shimon Peres was leading opinion polls and was projected to win the election by exit polls, Benjamin Netanyahu won by a margin of 29,457 votes, less than 1% of the total number of votes cast.

#### Malaysia

* 2018 House of Representatives election: the opposition Pakatan Harapan coalition won an absolute majority of 113 seats in the Dewan Rakyat (lower house of parliament), thus ending the 61-year rule of the Barisan Nasional coalition and bringing about the first change of a ruling party in the country's history.

#### Netherlands

* 2023 general election: The results of the election were described as "one of the biggest political upsets in Dutch politics since World War II", with the right-wing populist Party for Freedom (PVV), led by Geert Wilders, becoming the largest party in the House of Representatives.

#### Pakistan

* 2024 general election: The PML-N party led by three-time former Prime Minister Nawaz Sharif was viewed as the favourite to win, with Sharif expected to easily become Prime Minister for a fourth time. Sharif was perceived as the favourite of the powerful military establishment, likely to counter their common adversary, jailed former Prime Minister Imran Khan. Despite this, candidates affiliated with Khan’s PTI party emerged as the largest group on election night. This was seen as an exceptionally unlikely outcome, since the party was forced to field their candidates as independents after an unfavourable ruling in the Supreme Court, which severely limited their campaigning operations.

#### Poland

* 2015 presidential election: The incumbent Bronisław Komorowski was leading nearly all opinion polls taken before the first round of the election, with some polls taken in late 2014 and early 2015 suggesting he was on track for an outright win that would avoid a runoff election. Andrzej Duda eventually took a narrow first-place finish over Komorowski and went on to win the election in the runoff.

#### Romania

* 2024 Romanian presidential election (first round, later annulled due to intelligence reports of Russian interference): Călin Georgescu, a pro-Russian, anti-NATO, and far-right independent candidate, achieved a relative majority of votes, while Elena Lasconi of the centre-right Save Romania Union finished second and also advanced to the runoff vote. Initially viewed as a minor candidate with little chance of victory due to his far-right views, Georgescu quickly gained significant support through campaigning on non-traditional media outlets such as TikTok, receiving particular popularity among those disaffected with current Romanian politics, including youth, farmers, rural voters, and members of the working class. He was then considered the front-runner in the race, and polling conducted after the first round of voting found him to be the most popular figure in the country's politics. The aftermath of the first round was controversial and led Romania to the brink of a political crisis. Incumbent president Klaus Iohannis and chair of the Supreme Council of National Defence accused Georgescu's campaign of being supported by Russia. Following vote rigging allegations made by a minor candidate, the Constitutional Court of Romania ordered a recount; it ultimately decided to confirm the results of the first round on 2 December. On 6 December, the Constitutional Court reversed their decision and annulled the first round of the election after intelligence documents were declassified stating that Russia had run a coordinated online campaign to promote Georgescu.

#### Serbia

* 2012 presidential election: Tomislav Nikolić of the Serbian Progressive Party defeated Boris Tadić of the Democratic Party, who had recently resigned as the president of Serbia in order to trigger an early election. Nikolić had previously lost to Tadić in two elections.

#### Slovakia

* 2004 presidential election: Ivan Gašparovič finished as the runner-up over front-runner Eduard Kukan and advanced to run-off against Vladimír Mečiar whom he eventually defeated. Reportedly, Gasparovič himself did not expect to be a runner-up as he went home to sleep after he cast his vote.

#### Slovenia

* 2012 presidential election: Borut Pahor received the highest number of votes in the first round despite the incumbent president Danilo Türk leading opinion polls. Pahor then defeated Türk in the runoff.

#### Sri Lanka

* 2015 presidential election: Two-term strongman president Mahinda Rajapaksa of the ruling United People's Freedom Alliance lost his bid for a third term to opposition candidate Maithripala Sirisena.

#### Turkey

* 2023 general election: Opinion polls and media outlets implied incumbent AKP president Recep Tayyip Erdoğan was likely to lose to Kemal Kılıçdaroğlu, the CHP opposition candidate fielded by the Nation Alliance, amid fallout from the ongoing economic crisis and the February 2023 Turkey–Syria earthquakes. Erdoğan ultimately secured 49.5% of the vote against Kılıçdaroğlu's 44.9% in the first round of the presidential election, and won the runoff by a margin of 4.36%.

#### United Kingdom

* 1945 general election: The universal expectation that successful wartime leader Winston Churchill would win the first poll following the defeat of Nazi Germany in the Second World War was shattered by the overwhelming landslide victory of the Labour Party, raising Clement Attlee to the post of Prime Minister.
* 1970 general election: Most opinion polls prior to the election indicated a comfortable victory for the incumbent Labour government. On election day, however, a late swing gave the Conservatives a 3.4% lead and ended almost six years of Labour government.
* 1992 general election: the ruling Conservative Party won a fourth consecutive absolute majority in the House of Commons, despite opinion polls having predicted a hung parliament or a narrow absolute majority for the opposition Labour Party.
* 2015 general election: the Conservative Party, for the previous five years part of a coalition government with the Liberal Democrats, went on to win a majority in the House of Commons despite most polls predicting a hung parliament.
* 2017 general election: the ruling Conservative Party lost its absolute majority in the House of Commons, despite opinion polls predicting that they would keep it or even increase it.

#### United States

* 1948 presidential election: Incumbent Democratic President Harry Truman was re-elected over Republican New York governor Thomas E. Dewey, who had been leading in opinion polls. The upset led to the incorrect headline "Dewey Defeats Truman" being published by the Chicago Daily Tribune.
* 1964 United States Senate election in Ohio 75-year-old senator Stephen Young was re-election to his senate seat Against Republican Congressman Robert Taft Jr..
* 1972 United States Senate election in Delaware: Incumbent Republican senator J. Caleb Boggs was unexpectedly defeated by Democratic candidate (and future president) Joe Biden.
* 1982 United States Senate election in New Jersey Congresswoman Millicent Fenwick was widely expected to win the senate seat being vacated by Nicholas F. Brady, however she lost to Democratic businessman to Frank Lautenberg, Despite leading in all polls.
* 1990 United States Senate election in Minnesota: Republican senator Rudy Boschwitz ran for reelection to a third term, being defeated by Democrat Paul Wellstone.
* 1991 United States Senate special election in Pennsylvania In a special election to finish the remaining three years of the late Republican Senator John Heinz’s term, former governor and then U. S. Attorney General Dick Thornburgh was at one point leading By over 40 percentage points but ended up losing by 10% to Democrat Harris Wofford, Governor Bob Casey Sr.'s interim appointment to fill the vacancy.
* 1998 Minnesota gubernatorial election: Reform nominee and former wrestler Jesse Ventura was elected governor of Minnesota over Democratic nominee Skip Humphrey and Republican nominee Norm Coleman, despite Ventura having trailed behind both in pre-election polling.
* 2002 Georgia gubernatorial election: Incumbent Democratic governor Roy Barnes was widely expected to win a second term but was defeated by Republican Sonny Perdue who became the first Republican governor of Georgia since reconstruction.
* 2006 Iowa's 2nd congressional district election, Incumbent Republican representative Jim Leach lost his seat to democratic Challenger Dave Loebsack.
* 2008 United States House election in Louisiana’s 2nd congressional district: Controversial Democratic incumbent William J. Jefferson was defeated in his bid for reelection by Republican Joseph Cao .
* 2010 United States House election in Illinois’s 8th congressional district: Incumbent Democrat Melissa Bean sought reelection to a fourth term but was unseated by Republican Joe Walsh.
* 2014 United States House election in Virginia's 7th congressional district Republican primary: Republican Dave Brat defeated the U.S. House Majority Leader, Eric Cantor, in the 2014 Republican primary. His primary victory was the first to oust a sitting House majority leader since the position's creation in 1899. Brat went on to win the 2014 general election.
* 2014 Maryland gubernatorial election: Republican Larry Hogan was elected governor of Maryland over Democrat Anthony Brown despite pre-election polling which had Brown in the lead, and Brown falsely declaring victory days before the election.
* 2016 presidential election: Republican businessman Donald Trump was elected president over Democratic nominee Hillary Clinton, despite many media outlets showing her leading in both national and statewide opinion polls.
* 2016 North Dakota gubernatorial election: During the Republican primary, it was widely expected for longtime Attorney General Wayne Stenehjem to win. Despite winning the North Dakota Republican Party endorsement and leading numerous polls, Stenehjem was defeated in the primary by businessman Doug Burgum, who would go on to win the general election.
* 2018 United States House election in California's 21st congressional district: Republican incumbent David Valadao ran for reelection against Democrat TJ Cox. Initially, it appeared that Valadao had been reelected; however, after all the votes were counted, it was concluded that Cox had actually won.
* 2018 United States House election in Oklahoma's 5th congressional district: Incumbent Republican congressman Steve Russell ran for reelection to a third term, losing to Democrat Kendra Horn.
* 2018 New York's 14th congressional district election Democratic primary, Chair of the House Democratic Caucus Joe Crowley unexpectedly lost the primary for his house seat to Progressive activist Alexandria Ocasio-Cortez who also defeated him and Republican nominee Anthony Pappas in the general election
* 2020 United States House election in Florida's 27th congressional district: Incumbent Democratic congressman Donna Shalala sought re-election to her house seat against Republican María Elvira Salazar. Despite being the heavy favorite, Shalala was unseated by Salazar.
* 2022 United States House election in Washington's 3rd congressional district: In spite of pre-election predictions describing this seat as being a likely Republican hold, Democratic candidate Marie Gluesenkamp Perez defeated Republican candidate Joe Kent.
* 2024 United States Senate election in Pennsylvania Sitting Democratic Senator Bob Casey Jr. sought re-election to a fourth term in office, but lost to Republican nominee Dave McCormick. Most predictions gave Casey the advantage, and he led in most polls.
* 2024 Nebraska's 2nd congressional district election Incumbent Republican congressman Don Bacon was re-elected against Democrat Tony Vargas, Despite the fact that he had trailed Vargas in polling before the election .