WASHINGTON ( CNN ) -- Debates are a campaign 's restart button . Voters try to erase their preconceptions and examine the candidates face-to-face , equal and unscripted -- which is why a challenger , particularly one who 's running behind , is eager to have as many debates as possible . Voters said John Kerry won the debates in 2004 but they liked George W. Bush better and he won a second term . `` Let 's meet every week from now until the election and talk about the real issues facing Americans . '' That was John Kerry to U.S. President George W. Bush in August 2004 . Republican John McCain issued the same challenge to Democratic Barack Obama this summer , when Obama was the frontrunner in the polls . This year there 's three debates between the presidential candidates -- September 26 in Mississippi ; October 7 in Tennessee and October 15 in New York state . Debates are valuable because they provide most of the spontaneous moments in the campaign . Everything else is staged -- the rallies , the television ads , the conventions . But debates , which are organized by the bipartisan Commission on Presidential Debates , are unscripted . The candidates do not know the questions in advance . How do they prepare ? Debate coaches grill them . They ask them tough questions on every subject likely to come up . They even coach the candidates on `` body language , '' such as how to invade an opponent 's space in order to appear dominant . Watch a preview of the upcoming presidential debate » . In every election since 1952 -- until this year -- either the president has run for re-election ( like George W. Bush in 2004 ) or the vice president has run to succeed him ( like Al Gore in 2000 ) . Debates give the challenger a chance to close the stature gap with the president or the vice president . And to make the election a referendum on the incumbent president . In 1960 , John F. Kennedy , who was challenging Vice President Richard Nixon , played to concerns that the U.S. was losing its competitive edge against the Soviet Union . `` Are our strength and prestige rising ? '' Kennedy asked in a debate . `` Do people want to be identified with us ? '' The 1980 race was very much in doubt when challenger Ronald Reagan went into his one and only debate with President Jimmy Carter one week before Election Day . Reagan 's hard-line image frightened many voters . He used the debate to reassure them that he was n't a dangerous man . And to frame the election as a referendum on his opponent . `` Ask yourself , are you better off than you were four years ago ? '' Reagan said in his closing statement . `` Is it easier for you to go and buy things in the stores than it was four years ago ? Do you feel that our security is as safe , that we 're as strong as we were four years ago ? '' Debates often provide revealing moments . Like when President Gerald Ford prematurely liberated Eastern Europe at a 1976 debate . `` The United States does not concede that these countries are under the domination of the Soviet Union , '' the president said , making specific reference to Poland , Yugoslavia and Romania . In 1988 , Michael Dukakis gave a dispassionate response when asked whether he would favor the death penalty for someone who raped and murdered his wife . `` I 've opposed the death penalty all of my life , '' Dukakis replied . `` I do n't see any evidence that it 's a deterrent . '' In 1992 , the first President Bush was criticized for being out of touch with ordinary Americans . That perception was reinforced during a debate when the camera caught the president looking at his watch as he took questions from voters . One voter asked about the consequences of the national debt . `` I 'm not sure I get it , '' President Bush responded . The challenger got it . `` Tell me how [ the debt ] has affected you ? '' Bill Clinton responded . `` Do you know people who have lost their jobs and lost their homes ? '' In 2000 , Al Gore may have won more debating points . But the camera caught Gore theatrically sighing while George W. Bush answered questions . Voters liked Bush better . And that 's what counted . Similarly in 2004 , when CNN polled viewers after each debate , the prevailing view was that Kerry won . Voters concluded Kerry was a better debater than Bush . But that did n't get Kerry many votes . Voters decide how to vote based on many qualities , not just debating skills . The prize for winning a debate is not winning the election . What debates really do is keep the race open . Many voters say : `` I 'm going to hit the restart button , clear the screen and watch the debates with an open mind . Then I 'll decide how to vote . ''
Republican John McCain and Democrat Barack Obama are having three debates . Debates provide spontaneous moments and often provide revealing moments . They give voters the chance to examine the candidates face-to-face and equal . But winning the debate does not necessarily mean winning the White House .