On Friday, presidential candidates Barack Obama and John McCain are scheduled to hold the first of three debates ahead of November's election. Presidential debates have often played a crucial role in U.S. election campaigns in the past, as we hear from VOA National Correspondent Jim Malone.
The first televised presidential debate was held during the election campaign of 1960.
"The candidates need no introduction," said the debate moderator Howard K. Smith. "The Republican candidate is Vice President Richard M. Nixon and the Democratic candidate is Senator John F. Kennedy."
Kennedy's youthful appearance helped him on television. Nixon suffered from a cold and bad makeup.
"I think in the final analysis, it depends on what we do here. I think it is time America started moving again," Kennedy said.
"There is no question but that we cannot discuss our internal affairs in the United States without recognizing that they have a tremendous bearing on our international position," said Nixon.
Those who watched the debates on television generally thought Kennedy was the winner. Many of those who listened on radio gave the edge to Nixon.
Kennedy narrowly won the election that year. And even though Nixon eventually won two presidential elections in 1968 and 1972, he never took part in another presidential debate.
In the 1976 election campaign, incumbent Republican President Gerald Ford trailed badly in the polls for much of the year behind his Democratic challenger, Jimmy Carter.
Ford nearly came back to win the election that year, but stumbled in one of his debates with Carter when he tried to argue that Eastern Europe was not controlled by the Soviet Union.
"There is no Soviet domination of Eastern Europe and there never will be under a Ford administration," he said.
While much attention is paid to what is said in the debates, they can also be won or lost based on how the candidates speak and even their non-verbal body language.
In the 1992 debates with Democrat Bill Clinton and Independent candidate Ross Perot, then President George H. W. Bush appeared bored with the discussion and at one point was caught on camera looking at his watch.
In 2000, Democrat Al Gore let out a loud sigh while his opponent, then Texas Governor George W. Bush, was answering a question.
Most of the time, presidential debates feature the candidates repeating the same policy talking points they have uttered over and over again on the campaign trail.
But there are moments when one candidate or another is able to crystallize for voters what is at stake in the election.
Such a moment came in a 1980 debate when Republican Ronald Reagan took on President Jimmy Carter.
"Next Tuesday is the election day, all of you will go to the polls and stand there in the polling place and make a decision," he said. "I think when you make that decision, it might be well if you ask yourself, 'Are you better off than you were four years ago?'"
Political analyst Norman Ornstein says that moment proved crucial for Reagan as he tried to convince voters that he was up to the job of being president.
"And it wasn't really until we had that debate, just barely 10 days before the election, where Reagan went head-to-head in that direct comparison with Carter and not only reframed the election, as in 'Are you better off now than you were four years ago?' But he also showed that he was anything but some crazy man and that he was a reasonable person who could stand toe-to-toe with the President of the United States and more than hold his own that we saw the poll numbers change pretty dramatically over the closing days of the campaign," he said.
Reagan is also remembered for his humor in presidential debates. After a poor performance in his first debate in his 1984 bid for re-election, Reagan chose to make fun of his age during his second debate with Democrat Walter Mondale.
"I will not make age an issue in this campaign," he said. "I am not going to exploit for political purposes my opponent's youth and inexperience."
Mondale laughed along with the audience.
After the debate, Mondale told his wife that he was almost certain that he was going to lose the election that year. He was right. Reagan went on to a landslide re-election victory.
Incumbent: currently holding a specified office（现职的）