A debate spelled the end for Biden. For Trump and Harris, the stakes are sky high

WASHINGTON − When the history of the 2024 presidential election is written, the one and only debate between Joe Biden and Donald Trump will be remembered as the event that truly changed the course of the race.

A few weeks after Biden’s disastrous performance, he dropped out , and Kamala Harris stepped in as the Democratic nominee.

This week, the second debate of the presidential contest will take place, this time between Harris and Trump. The stakes are high for both candidates; polls show a close race with just two months left until Election Day.

For Harris, Tuesday's debate in Philadelphia will provide a chance to show she can stand up to Trump and introduce herself to voters who feel they know little about her. For Trump, the debate is an opportunity to define Harris on his terms and try to regain some of the momentum he lost to her after the Democratic National Convention in Chicago.

In a race this close, a strong debate performance could give either candidate an edge going into the final weeks of the campaign. But don’t expect this debate to be as earthshaking or as game-changing as the Biden-Trump confrontation June 27

“We’re not going to see anything that dramatic happen again,” said David Greenberg, a history professor at Rutgers University and an expert on presidential debates.

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Few presidential debates have a major impact on the race. But that doesn’t mean debates don’t matter, experts said.

Though she has been Biden’s vice president for nearly four years, Harris is still relatively unknown to many voters. Americans who didn’t see Harris’ well-received speech at the Democratic convention in Chicago may tune in to the debate to learn more about her. The same is true for independent or undecided voters still seeking information to help them make up their minds.

Harris is “on a very positive trajectory at the moment – she has the wind at her back,” said Alan Schroeder, who has written several books about presidential debates. “What’s next? Can she sustain that? Can she build on that? Or does this prove to be a false illusion? This debate … gives her a chance to sort of demonstrate who she is to people in a context that can be tricky.”

Given the abbreviated time frame Harris has to make her case, the debate probably carries more weight than a typical presidential debate, said Dustin Carnahan, a Michigan State University associate professor who specializes in political engagement.

Biden exited the race and Harris stepped in just four months before Election Day. Since then, “the Harris campaign has really crammed in a lot of events that typically do generate positive news coverage, as well as the fact that the party has really coalesced around her,” Carnahan said. “In a sense, the debate might be the end of the honeymoon.

“This is where it’s pretty critical for the Harris campaign to convince people – getting into things like policy, where she’s already starting to get some criticism,” Carnahan said. “What will she do if she’s elected? She’s going to have to answer those questions, and the debate is going to be a really important opportunity for her to do that.”

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In Trump’s case, voters already know who the Republican nominee is and have come to expect erratic behavior from him. But while he has been able to bluster his way through debates with other GOP candidates during the primaries, he hasn’t been as successful when put on stage with his Democratic opponents in the general election.

In 2016, Trump didn’t do particularly well in his three debates against Hillary Clinton , Schroeder said. He won the debate with Biden by default: It was Biden’s uneven performance – not an especially strong showing by Trump himself – that drove Biden out of the race, Schroeder said.

The challenge for Trump “is to rein it in as best as he can and not cross the line into disrespect when he has a female candidate, a nonwhite candidate,” Schroeder said, “because Trump has shown himself to be uncomfortable in handling those topics.”

Every now and then, a presidential debate can make a difference.

The most famous example is probably the first televised presidential debate, which was between Democrat John F. Kennedy and Republican Richard Nixon in 1960. The telegenic Kennedy, just 43 at the time, wore makeup and projected youthfulness and vigor to the TV audience. Nixon, just four years older than Kennedy, refused to put on makeup, sweated profusely under the hot television lights, and appeared old and tired.

Viewers who watched the debate on TV thought Kennedy had won, while those who listened to it on the radio gave the edge to Nixon. Kennedy won the presidency in one of the closest races in history. He later conceded he probably would not have won had it not been for the debate.

Sixteen years later, in 1976, Republican President Gerald Ford seriously damaged his campaign when he insisted during a debate with Democrat Jimmy Carter that there was no Soviet domination of Eastern Europe. Ford probably would have lost anyway, analysts say, but his gaffe solidified the public’s image of him as a bumbler-in-chief who was grossly out of touch with reality. He was never able to recover.

In 1980, Republican Ronald Reagan effectively used his only debate with Carter to dispel the perception that he was a radical warmonger by coming across as amiable and talking of peace. In one of the most memorable lines ever spoken during a presidential debate, Reagan tapped into voters’ concerns about high inflation by asking viewers, “ Are you better off than you were four years ago?”

A week later, Reagan scored a landslide victory over Carter, who won just six states and the District of Columbia.

“That (debate) made a difference to a lot of Americans,” Greenberg said.

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More recently, then-Vice President Al Gore , who was considered the superior debater, sighed loudly, rolled his eyes and shook his head during a debate with then-Texas Gov. George W. Bush ahead of the close 2000 election. Voters told pollsters they disliked Gore’s personality, his small lead against Bush vanished, and he lost the super-close election, which was ultimately decided by the Supreme Court.

Eleven years later, then-Texas Gov. Rick Perry mortally wounded his campaign when, during a debate with other GOP candidates ahead of the 2012 primaries, he famously could not remember one of the three government departments he had vowed to eliminate if elected. A couple of months later, he withdrew from the race.

No presidential debate, though, has had the catastrophic impact on a candidate as the showdown between Biden and Trump last June.

“The entire race was turned upside down as a consequence of Biden’s performance,” Carnahan said.

Biden not only failed to address concerns about whether he was physically and mentally capable of serving a second term, he “reinforced to much of an extent the concerns that people, that voters, that individuals within his own party were having around his ability to make it through the 2024 election cycle,” Carnahan said.

“That was something we will probably be hard-pressed to see happen again.”

Michael Collins covers the White House. Follow him on X @mcollinsNEWS.

This article originally appeared on USA TODAY: A debate spelled the end for Biden. For Trump and Harris, the stakes are sky high