从图表的结果来看，1992年辩论之后的赢家是Perot，比尔反倒失掉了几个百分点。 http://www.gallup.com/poll/110674/Presidential-Debates-Rarely-GameChangers.aspx
PRINCETON, NJ -- Gallup election polling trends since the advent of
televised presidential debates a nearly a half-century ago reveal few
instances in which the debates may have had a substantive impact on election
outcomes. The two exceptions are 1960 and 2000, both very close elections
in which even small changes could have determined who won. In two others --
1976 and 2004
