Barack Obama was widely considered the probable Democratic nominee in March.

Instead of voters rallying to him, as they often do with winners, Obama went on to lose nine of the final 16 primary contests, five by double digits.

This suggests that Democrats may have experienced a case of buyer's remorse. One reason for such remorse could be a realization that if he is elected president, Sen. Obama would be the least qualified and experienced man to hold the office in modern times. This is not a criticism or a value judgment, but rather an observation of fact.

Since the Civil War, 49 men have won a major-party presidential nomination. Only three of these nominees were less qualified, by traditional measures of leadership and experience, than Obama.

In the 1872 election, Horace Greeley, backed by the Liberal Republicans and Democrats, was a dilettante newspaper publisher. In his first presidential run in 1896, William Jennings Bryan's only credentials were two terms in the House of Representatives and the ability to give a great speech. (Sound familiar?) Wendell Willkie, who served as FDR's punching bag in 1940, was nothing but a corporate lawyer and Republican Party apparatchik.

None of those men was able to win the White House. But inexperience is not necessarily an electoral liability. Bill Clinton, a draft-dodging state attorney general and governor, bested a sitting president who had served as vice president, congressman, ambassador, and head of the CIA (not to mention being a hero in World War II).

Or consider George W. Bush, who hid out in the Texas Air National Guard during Vietnam before going on as an adult to a string of business failures. He had only six years in public life as governor of Texas, an office with relatively little executive power.

Bush defeated Al Gore (who served in Vietnam, spent 22 years in Congress, and was vice president) and John Kerry (a decorated Vietnam veteran who had been a district attorney and lieutenant governor before spending 20 years in the U.S. Senate).

So Obama may well beat John McCain, even though McCain's résumé trumps his by every traditional measure of leadership and experience.

But while inexperience is no bar to office, it may not be an asset once the governing begins. Part of Obama's pitch is that his relative inexperience will allow him to approach the problems of governance with a fresh set of eyes. This may prove to be true. But two other recent presidents sought office using that same argument: Jimmy Carter and George W. Bush. Neither of their administrations was covered in glory.

Without experience, a president is hostage to both his advisers and his inner compass. A naïf in matters of economics and foreign policy, Carter was unable to distinguish the bad advice he received about the energy crisis, managing inflation, and the rising Islamic radicalism in Iran.

Bush campaigned as a post-partisan uniter who could get things done because he hadn't been corrupted by Washington. But he couldn't sniff out the bad advice he received from George Tenet and Donald Rumsfeld.

Yet despite, or perhaps because of, their inexperience, Carter and Bush shared an overwhelming confidence in the rightness of their own judgments. Both were, as the expression goes, "comfortable in their own skin" - meaning that they were happy to make decisions based on gut instinct.

Think of it as the presidential version of Malcolm Gladwell's Blink hypothesis that the instant conclusions we reach are often the best ones. This contributed in no small way to their failed presidencies.

In terms of Obama's accomplishments, his sense of self, and his insistence that good judgment is more important than experience, his candidacy bears more than a passing resemblance to the candidacies of Carter and Bush.

That's not a particularly happy thought, so let's end with a sunnier possibility.

There was one other notably inexperienced president during the modern era: Abraham Lincoln spent just eight years as a state legislator and two years in Congress before winning the White House.

Granted his candidacy was centered on an idea somewhat more substantial than Obama's calls for Hope and Change. But who knows? If America decides to roll the dice on a President Obama, maybe we'll get lucky.

E-mail Jonathan Last

at jlast@phillynews.com.