总统辩论意在说服犹豫不决的选民

WASHINGTON — Debates between the major political parties’ nominated presidential candidates have become a pre-election fixture in the United States. This segment of "How America Elects" examines the impact of these debates as Election Day in November approaches.

By October, each major party's presidential candidate has locked in many supporters. But there are still undecided people to persuade, whose votes may well decide the election. The debates between the presidential candidates - usually three in number - and the one for the vice presidential contenders, serve as “the home stretch” in the race to the White House.

For most of the campaign season, the candidates put forth their positions in short statements meant for easy play on TV. Before many voters mark a ballot, though, they want the White House contenders to give them more details on the major issues. The debates are meant to provide that opportunity, said Georgetown University professor Mark Rom.

“This is a chance for them to show their vision, to talk about their goals, their dreams, their hopes for the American people. And to suggest to the American people how they will fulfill those dreams,” said Rom.

While these candidate clashes are called debates, the way they are conducted more closely resembles an interview. Government professor Candice Nelson at American University described the way it works.

"For two of the three presidential debates, and the vice presidential debate, there will be a single moderator who will pose questions to each of the candidates. And the opposite candidate will have a chance to respond to what the first candidate who answers the question says. The thinking is [that] by having a moderator there, it is a way to control the debate to make sure that the questions get answered fairly," said Nelson.

The two moderated debates are separated into domestic and foreign policy. The third is done in a so-called "town hall" format where citizens ask questions on any category.

Today’s televised debates have been a part of every presidential election since 1976, but also took place in 1960, when Democratic Senator John Kennedy and the Republican Vice President, Richard Nixon, squared off.

One candidate who used the debates to great effect was Republican Ronald Reagan. In 1980, he posed a question that some say helped to defeat the incumbent, Democratic President Jimmy Carter.

"I think [that] when you make that [voting] decision, it might be well if you ask yourself 'Are you better off [today] than you were four years ago?'" said Reagan.

These debates also can be part of a candidate’s own undoing. In his 1976 debates with Democrat Jimmy Carter - at the height of the Cold War - Republican incumbent President Gerald Ford made a stunning misstatement.

“There is no Soviet dominance of Eastern Europe, and there never will be under a Ford administration,” said Ford.

Ford was ridiculed for saying that. Pundits say the statement contributed to his loss to Jimmy Carter.