In his 1980 challenge to President Jimmy Carter, Ronald Reagan pulled off two famous debate lines that helped win a landslide. "There you go again," he quipped when Carter accused him of planning Medicare cuts. And he asked America a question that still echoes today: "Are you better off now than you were four years ago?"
Reagan's shaky performance in the first debate of 1984 raised questions about the 73-year-old president's fitness for another term. Next round, when asked about the age issue, Reagan silenced doubters by declaring with a twinkle that he would not "exploit for political purposes my opponent's youth and inexperience."
At that moment, "the campaign was over," the Democratic nominee, Walter Mondale, later told PBS journalist Jim Lehrer.
Debates rarely yield such total triumphs, however. And they're seldom an election's single deciding factor, scholars such as McKinney say.
President Gerald Ford's insistence in 1976 that "there is no Soviet domination of Eastern Europe" undermined confidence in his ability as a Cold War leader. Texas Gov. Rick Perry wiped out his chance at this year's Republican nomination by forgetting the third of three federal agencies he wanted to eliminate. All he could say was, "Oops."
Although it doesn't happen often, McKinney said, "There is a chance to blow it."
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