WASHINGTON -- For all their talk about respecting the constraints of reality, conservatives generally hold to the great man theory of history. It is leftists who embrace economic determinism. Conservatives read biographies of Winston Churchill and wait in constant expectation for the second coming of Ronald Reagan. Charisma and truth, in this view, can always overwhelm material conditions.

And this often leads to the small man theory of electoral setbacks. A losing Republican is not merely unfortunate; he must be incompetent, politically blind, and betrayed by his bumbling underlings. If he is not a winner, he is a fool.

John McCain has reached this stage of criticism among conservatives. Some attack him for "frenetic improvisation," while others urge him to frenetically improvise. His campaign is in a "defensive crouch" while also being "obnoxious" in its "phony populism." McCain's running mate is a "fatal cancer" who should "read more books."

This kind of cheap shot is, thank goodness, the prerogative of the commentator -- an option I will doubtlessly exercise in the future. But having once been on the political side of the divide, I remember how truly obnoxious such advice can become. If only the candidate would fire his entire campaign staff and travel the country in a used Yugo, speaking in the parking lots of 7-11s, the gap would be closed. If only the candidate would buy three hours in prime time and give a bold, historic speech (which has been helpfully sent under separate cover), the entire election would be turned around. If only the candidate would finally highlight his opponent's ties to Colombian drug cartels, the illuminati and the British royal family -- or perhaps abandon all this suicidal negativity -- the election could certainly be won. And yes, above all, the candidate must be himself.

McCain might benefit from shifts in strategy: a retooled stump speech has already been rolled out. But sometimes a candidate down in the polls is not an incompetent but a bystander. While America remains a center-right country, this may well be a Marxist election in which economic realities are determining the political superstructure.

The diverging political fortunes of Barack Obama and McCain can be traced to a single moment. In the middle of September, the net favorable rating for each candidate was about the same. By Oct. 7, Obama was ahead on this measure by about 16 points. Did McCain suddenly become a stumbling failure? No, the world suddenly went into an economic slide. Americans blamed the party with executive power, which is also the party most closely tied in the public mind to bankers and Wall Street. None of this was fair to McCain, who has never been the Wall Street type. But party images are vivid, durable and almost impossible to shift on short notice.

Previous to this economic free fall -- and after his transformative vice presidential choice -- McCain was about tied in a race he should have been losing by a large margin. The public clearly had questions about Obama's leadership qualities. But the McCain campaign also proved itself capable of constructing an effective narrative: Obama as lightweight celebrity, McCain as maverick reformer. Until history intervened.

Following the onset of the crisis, McCain was left with flawed options. He reasonably chose to work for a responsible bailout while hoping the markets would stabilize quickly. Instead, the bailout proved politically unpopular and the markets gyrated like the Pussycat Dolls. Then McCain raised Obama's past association with William Ayers -- a valid attack if properly raised. (Can anyone doubt that the past political association of McCain with a right-wing terrorist would attract some attention?) But this accusation naturally looks small compared to the nation's outsized economic fears.

Obama's task has been easier. He needs only to ride a historical current instead of fighting it. And this plays to his greatest political strength: the easy, laid-back, self-assurance of a 1940s crooner. During the financial crisis Obama has contributed nothing of note or consequence. His only recent accomplishment has been to say questionable things in the debates -- attacking Republicans and capitalism for a credit meltdown congressional Democrats helped to cause, blaming America for Iran's nuclear ambitions, talking piously about genocide prevention when his own early Iraq policies might have resulted in genocide -- all while sounding supremely reassuring and presidential.

Obama's current success is not enjoyable for conservatives. But this does not make McCain an incompetent. Maybe he is a great man running at the most difficult of times.