Justice Oliver Wendell Holmes said that a good catchphrase could stop thinking for 50 years. One of the often-repeated catchphrases of our time -- "It's the economy, stupid!" -- has already stopped thinking in some quarters for a couple of decades.
There is no question that the state of the economy can affect elections. But there is also no iron law that all elections will be decided by the state of the economy.
Pres. Franklin D. Roosevelt was reelected for an unprecedented third term after two terms in which unemployment was in double digits for eight consecutive years.
We may lament the number of people who are unemployed or who are on food stamps today. But those who give the Obama administration credit for coming to their rescue when they didn't have a job are likely to greatly outnumber those who blame the administration for their not having a job in the first place.
An expansion of the welfare state in hard times seems to have been the secret of FDR's great political success in the midst of economic disaster. An economic study published in a scholarly journal in 2004 concluded that the Roosevelt administration's policies prolonged the Great Depression by several years. But few people read economic studies.
This economy has been sputtering along through most of the Obama administration, with the unemployment rate hovering around 9 percent. But none of that means that Barack Obama is going to lose the 2012 election.
Even polls that show "any Republican" with more public support than Obama do not mean that Obama will lose.
The president is not going to run against "any Republican." He is going to run against some specific Republican, and that Republican can expect to be attacked, denounced, and denigrated for months on end before the November 2012 elections -- not only by the Democrats, but also by the media, which is heavily pro-Democrat.
We have already seen how unsubstantiated allegations from women with questionable histories have dropped Herman Cain from front-runner status to third place in just a couple of weeks.
In short, it takes a candidate to beat a candidate, and everything depends on what kind of candidate that is.
The smart money inside the Beltway says that the Republicans need to pick a moderate candidate who can appeal to independent voters, not just to the conservative voters who turn out to vote in Republican primaries. Those who think this way say that you have to "reach out" to Hispanics, the elderly, and other constituencies.
What is remarkable is how seldom the smart-money folks look at what has actually been happening in presidential elections.
Ronald Reagan won two landslide elections when he ran as Ronald Reagan. Vice President George H. W. Bush then won when he ran as if he were another Ronald Reagan, with his famous statement, "Read my lips, no new taxes."
But after Bush 41 was elected and turned "kinder and gentler" -- to everyone except the taxpayers -- he lost to an unknown governor from a small state.
Other Republican presidential candidates who went the "moderate" route -- Bob Dole and John McCain -- also came across as neither fish nor fowl and went down to defeat.
Now the smart money inside the Beltway is saying that Mitt Romney, who is nothing if not versatile in his positions, is the Republicans' best hope for replacing Obama.
If conservative Republicans split their votes among a number of conservative candidates in the primaries, that can mean ending up with a presidential candidate in the Bob Dole-John McCain mold -- and risking a Bob Dole-John McCain result in the next election.
The question now is whether the conservative Republican candidates who have enjoyed their successive and short-lived boomlets -- Michele Bachmann, Rick Perry, and Herman Cain -- are prepared to stay in the primary race to the bitter end, or whether their conservative principles will move them to withdraw and throw their support to another conservative candidate.
There has probably never been a time in the history of this country when we more urgently needed to get a president out of the White House, before he ruined the country. But will the conservative Republican candidates let that guide them?
Bio: Thomas Sowell is a senior fellow at the Hoover Institution and a regular contributor to National Review. The opinions expressed in this commentary are solely those of the author.