Why was Obama reelected? A prediction and a convincing explanation came from the authors of The Keys to the White House: Because American society basically judges and decides according to the incumbent’s experience in the previous four years.

If the American people are basically satisfied with their president’s performance, some quibbles notwithstanding, they ratify him in his post. If not, they fire him or reject his party, in the case of a second term. That rational factor weighs more than the advertising campaigns and the debates.

The authors of this model of prediction, which relies on no polls and assigns no vote percentages in the hypothetic result, are the American historian Allan Lichtman and Vladimir Keilis-Borok, a mathematician of Russian origin.

So far, they’ve made the right call in all the U.S. presidential elections to which they’ve applied their method (the past eight) and, if we believe them, have verified its infallibility in all the presidential elections since 1860, the first year for which they found sufficient information.

How does that crystal ball work? There are 13 fundamental questions upon which most Americans base their judgment on the convenience of changing (or not) the White House tenant. If the president fails in more than five, he will not be reelected. If he flunks fewer than five, the voters will give him another chance to serve.

Judging from this prediction model, Obama flunked only three questions and was therefore kept at the helm of the ship of state.

The 13 considerations are the following:

1. The president’s party increases the number of members of Congress in the mid-term elections, two years after being elected. (In the 2010 elections, Obama lost seats. His first failure.)

2. The president has no challengers within his own party who attempt to replace him. (Nobody challenged Obama.)

3. Incumbency. The candidate is also the title holder. (Obama is the incumbent.)

4. There is no third party with a significant electoral weight. (There isn’t. Ross Perot kept Bush Sr. from being reelected. Ralph Nader got 97,000 votes in Florida in 2000 and denied the presidency to Al Gore. That year, Bush won Florida — and the presidency — by 537 votes.)

5. A recession during the elections. (The U.S. is not in a recession. It has economic problems, but is not in a recession.)

6. The overall state of the economy. (In general, the economy has not grown as in the past and more problems loom on the horizon. The huge increase in the public debt is a very serious issue. Obama’s second failure.)

7. Major changes in government measures. (Actually, none have been made. The reform in the health system — mandatory health insurance — is not exactly a turning point, and the increase in taxes, if approved, would mean returning to the situation before George W. Bush.)

8. Major social conflicts. (None have occurred. The demonstrations by “the angry ones” have been considerably smaller than those in Europe and have been restricted to some protests on Wall Street.)

9. Scandals. (During its first four years, Obama’s administration did not experience any significant public or private scandal.)

10. Military failure. (Obama’s government has not suffered a notable military defeat or suffered a major terrorist act. The troops in Iraq will soon complete their withdrawal, as planned, and those in Afghanistan are preparing their departure.)

11. Military success. (The deaths of Osama bin Laden and other leaders of al Qaeda can be presented as victories in that department.)

12. The incumbent’s charisma or heroic profile. (Obama’s third failure. He is a good communicator but does not have the attractiveness or charisma of John F. Kennedy or Franklin Delano Roosevelt. Nor is he a hero, like Dwight D. Eisenhower. Rather, he is a held-back and discreet leader.)

13. The opponent’s charisma or heroic profile. (Mitt Romney didn’t project the image of a charismatic candidate, either, and was hardly perceived as a hero. He was an intelligent, decent, handsome fellow and a good businessman but not someone who connected emotionally with the masses.)

After doing the calculations, American society — though much divided — ratified its president. In the process, it proved The Keys to the White House right.