Mitt Romney’s winning performance in last week’s presidential debate has reinforced his campaign’s belief that this election parallels the one in 1980: In troubled times, Republicans inevitably defeat an unpopular Democratic president.

While Romney gets to hit the reset button after President Barack Obama’s desultory display, he’d better not count on the 1980 analogy. Ronald Reagan’s victory over Jimmy Carter wasn’t inevitable; it was earned, with some help from outsiders. The environment was far less hospitable for the incumbent president in 1980 than it is today.

Looking at the three major elements of any presidential contest ― the candidate and campaign, the conditions, and the electorate ― underscores the Republican’s challenge in replicating the Reagan victory this year.

Obama is a better candidate than Carter. Romney is no Reagan.

To be sure, the architects of the Carter campaign in 1980 were a little better than their Reagan counterparts and probably better than the Obama team this year. And candidate Reagan made some major mistakes, such as warning about the environmental damage caused by trees. He dispatched his running mate, George H.W. Bush, to China to burnish the ticket’s foreign-policy credentials even as he expressed support for Taiwan, resulting in a debacle reminiscent of Romney’s foreign travels last summer.

Yet, at crucial times, Reagan also was capable of inspiring moments; his eloquent convention speech gave him a big advantage in polls, in sharp contrast with Romney’s address this year. In the close of his debate with the president, after being on the defensive for much of the evening, Reagan blew Carter away.

And Carter matched Reagan mistake for mistake. Less than four weeks before the election, the Democrats had to arrange a special TV interview during which the president promised to cut out his mean rhetoric. After facing Senator Edward M. Kennedy in a bruising nomination battle, he was leading a divided party.

For all the talk about a lousy economic environment this year, things were much worse 32 years ago. The jobless rate had remained at the 7.5 percent level that Carter inherited (slightly lower than the 7.8 percent today). For the past three years, inflation and interest rates have been remarkably low and stable. Under Carter, the inflation rate more than doubled to 12.6 percent. A metric known as the Misery Index, the combination of inflation and unemployment, topped 20 percent on Election Day 1980. Today, it’s 9.5 percent.

The interest-rate picture was worse. Home-mortgage rates almost doubled and the federal-funds rate tripled. The month before the election, Carter had a job-approval rating of 37 percent; Obama’s hovers around 50 percent.

Republicans now are trying to make the case that the tragedy in Libya, where lax security may have contributed to the assassination of the U.S. ambassador, underscores Obama’s weakness on national security. That’s a tough sell against the commander in chief who ordered the successful mission to kill Osama bin Laden.

And it doesn’t begin to compare with the charges made against Carter in 1980, when 52 Americans were held hostage for 444 days after the takeover of the U.S. Embassy in Tehran. ABC News broadcast an award-winning nightly program on the crisis entitled “America Held Hostage: Day XXX.” The charge that America was impotent resonated in those Cold War days.

The demographics of the electorate also have shifted dramatically. In the Reagan victory, 88 percent of voters were white. In November, that number will be closer to 74 percent, and the president will capture about 80 percent of the nonwhite vote. Young voters split in the earlier election; this year, turned off by what they see as the Republican Party’s intolerance, they will vote decisively for Obama.

Even with these advantages, Reagan struggled during the fall. Three weeks before the election, his pollster, Richard Wirthlin, in a private campaign survey, found Carter ahead by two points.

It was Reagan’s command at the end of the debate, his strength as a closing candidate and, and perhaps most of all, the Iranians’ pulling out the rug from under Carter on the eve of the election that settled the contest.

Reagan trimmed some of his harder-line conservative positions in the general election. He altered his opposition to federal aid for New York City and Chrysler Corp. and enlisted establishment Republicans such as Henry Kissinger and Alan Greenspan.

These changes pale in comparison to Romney’s complete transformation since he first decided to run for president six years ago: he turned from a supporter of immigration reform to an immigration basher; from a champion of stem-cell research to an opponent, and most recently, he has moved away from the position on tax cuts he espoused in the primaries.

In the end, Reagan persuaded voters he had core principles and an ability to lead the country. One minor triumph in a debate is only a small step if Romney is to accomplish a similar journey. 

By Albert R. Hunt

Albert R. Hunt is Washington editor at Bloomberg News. The opinions expressed are his own. ― Ed.