Paul  Kengor
Mitt Romney lost the presidential race by only two percentage points. If the election had been held just a week earlier, when he was up in the polls, things might have been different. Nonetheless, Mitt Romney lost, and now a bitter debate has ensued over the future of the Republican Party, with liberal Democrats happily plunging into the debate.

What is being lost in this debate, however, is just how hard it is to defeat an incumbent president—any incumbent president. Here’s a history lesson from the last 100 years:

There have been 19 incumbent presidents since Teddy Roosevelt, including Barack Obama. The vast majority of them—14, to be exact—were reelected. Only five of them lost: William Howard Taft, Herbert Hoover, Gerald Ford, Jimmy Carter, and George H. W. Bush.

What about the five that lost? A look at their losses is instructive.

Taft lost in 1912 to Woodrow Wilson, who received only 42 percent of the vote. What killed Taft and the Republicans was Teddy Roosevelt’s entrance into the race, splitting the GOP and much of the country. Once that happened, Taft was doomed.

Herbert Hoover lost because of the Great Depression. In fact, Hoover’s loss is indicative of what prompts most defeats of presidential incumbents: bad economies. That’s a pattern that would hold repeatedly, with one glaring exception: President Obama.

After Hoover, no president lost a reelection bid until Gerald Ford in 1976. Ford had never been elected in the first place. He assumed the awful task of replacing a disgraced Richard Nixon. And the economy under Ford was not good.

Ford was beat by Jimmy Carter, who presided over a terrible economy. Words like “malaise” and “misery index” became household words to describe the Carter years. By 1980, the economy under Carter was clearly worse than four years earlier. Ronald Reagan beat him in a landslide, taking 44 of 50 states.