Editor's note: Jon Meacham, an executive editor at Random House, is the author of the forthcoming Thomas Jefferson: The Art of Power, to be published in November 2012. He wrote this piece for TIME Magazine. The views expressed are solely his own.
(CNN) -- Counterfactuals — the fancy term for historical What Ifs? — can be great fun. What if Harry Truman had been a successful haberdasher? What if Richard Nixon had been hired by an Eastern law firm? What if Ronald Reagan had gotten the job he wanted at Montgomery Ward back in Illinois, rather going into radio, which led him to cover the Cubs' spring training in southern California, which led to a screen test, and so on? (Reagan always thought the rejection from Montgomery Ward changed his life.)
The common theme here is the familiar Thomas Carlyle argument that human actions ultimately determine the course of history. (The tension between the Great Man theory and the school that argues for the primacy of geography, weather, and other supra-human factors is perennial, irreconcilable, and diverting.)
Given the latest political science on Campaign 2012, it's becoming clear that we might well paraphrase Huey Long and declare a new mantra for the next ninety days: Every Man (or Woman) a Great Man (or Woman).
According to a recent analysis by Larry M. Bartels and Lynn Vavreck for the New York Times, the bloc of influential undecideds is small but critical. And that handful tends to be more favorably disposed toward the Democratic Party, which suggests that they are more likely to wind up voting for President Obama than for Mitt Romney.
This is all speculative, of course, but one thing is clear: the race is most likely to be close to the very end, and these undecideds in key Electoral College states — Ohio and Virginia are essential — will make all the difference in the final count.
Which means that we are in a situation very much like 2000, where every vote will count—and any voter who stays home will have to ask the following question on the morning after: What if?
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