Republican President Donald Trump and Democrat Joe Biden face off on Tuesday in a televised presidential debate, part of a 60-year-old tradition marked by some of the most memorable moments of modern US political history:
1960: The first televised debate pitted Democratic nominee John F. Kennedy against Republican Vice President Richard Nixon, who was recovering from a hospital visit and had a 5 o'clock shadow, having refused makeup. The 70 million viewers focused on what they saw, not what they heard. Kennedy won the election.
1976: In the first TV debate in 16 years, Democrat Jimmy Carter faced unelected incumbent Republican President Gerald Ford. In remarks seen as a major blunder, Ford said: "There is no Soviet domination of Eastern Europe, and there never will be under a Ford administration." Carter won the election.
1980: Carter appeared in a second debate with Republican Ronald Reagan after boycotting the first for including third-party candidate John Anderson. The president accused Reagan of planning to cut Medicare healthcare funding for the elderly. Reagan, who already had complained that Carter was misrepresenting his stands on a number of issues, said: "There you go again" and chuckled, drawing audience laughter and coining a catchphrase. Reagan won the election.
1984: Reagan, 73, successfully defused the issue of his age when he debated Democrat Walter Mondale, 56, quipping: "I want you to know that also I will not make age an issue of this campaign. I am not going to exploit, for political purposes, my opponent's youth and inexperience." Reagan was re-elected.
1988: A debate against Republican Vice President George H.W. Bush opened with Democrat Michael Dukakis being asked whether he would favor the death penalty for someone who raped and murdered his wife. The question offered a candidate dubbed "the iceman" by critics a chance to show his emotional side. His laborious response did just the opposite. Bush won the election.
The vice presidential debate came alive when Dan Quayle, Bush's running mate, compared himself politically to John F. Kennedy. Democrat Lloyd Bentsen replied in quiet, deadly tones: "Senator, I served with Jack Kennedy. I knew Jack Kennedy. Jack Kennedy was a friend of mine. Senator, you're no Jack Kennedy."
1992: Three candidates - Bush, Democrat Bill Clinton and independent Ross Perot - shared a stage. Clinton won the election.
1996: In a debate with Clinton, Republican Bob Dole was asked by a student whether at 73 he was too old to understand the needs of young people. He replied that at his age, intelligence and experience meant he had the advantage of wisdom. Clinton retorted: "I can only tell you that I don't think Senator Dole is too old to be president. It's the age of his ideas that I question." Clinton was re-elected.
2000: In his first debate with Republican George W. Bush, Democratic Vice President Al Gore drew negative reviews for sighing loudly while Bush spoke. "We all make mistakes. I've been known to mangle a syllable or two myself," Bush said during their second debate, purposely mispronouncing "syllable." Bush won the election.
2004: The last debate between Bush and Democrat John Kerry offered voters a stark contrast in styles, with Bush sticking to simple arguments while Kerry released an array of facts to make his case. Bush was re-elected.
2008: Sarah Palin, Republican John McCain's running mate, and Joe Biden, running with Democrat Barack Obama, clashed on the economy and Iraq during a lively but polite vice presidential debate. Palin frequently displayed a folksy style. At one point, she said: "Aw, say it ain't so, Joe," adding a "doggone it" for good measure. Biden and Palin both vowed to make US economic policy friendlier for middle-class workers, but Biden said McCain had called the fundamentals of the economy strong as the financial crisis broke out. The Obama-Biden ticket won the election.
2012: Obama stumbled in his first debate with Republican Mitt Romney, surprising and worrying his supporters. But in their second debate Romney, responding to a question about gender pay equality, said he had "binders full of women" as candidates for Cabinet posts. The phrase became a meme on social media, with tweets, original artwork and a Facebook group spoofing Romney. Obama won again.
2016: The first debate between Donald Trump and Democrat Hillary Clinton drew 84 million US television viewers, a record for a debate and a rare number in an age of digital streaming. An exchange of insults dominated their second debate, with Clinton jabbing at Trump for sexually aggressive remarks about women he made on a just-uncovered 2005 videotape. Trump sought to deflect criticism by accusing Bill Clinton, the candidate's husband, of having done worse to women. In her book published in 2017, Clinton wrote that in their second debate Trump made her skin crawl by stalking her around the stage and she wondered if she should have told him to "back up, you creep." Instead she said, "I kept my cool, aided by a lifetime of dealing with difficult men trying to throw me off." In the third debate Trump called Clinton "such a nasty woman" and declined to say he would accept the election results.