The discussion on Monday morning’s “Daily Rundown” on MSNBC has already occurred hundreds of times this cycle and will occur again and again between now and November. Who is Mitt Romney?

Is the former Massachusetts governor the smart businessman who knows how to create jobs and fix the economy, or is he the rich investor who squeezed the last dime out of a business before shutting it down and throwing its workers out on the street?

Is he the phony, elitist flip-flopper who doesn’t have an agenda other than to get elected, the right-wing extremist and bully who will carry on the so-called war against women or the mainstream conservative who simply wants to control spending, hold the line on taxes and address the growth of entitlements to get the nation’s finances in order?

“Other people are defining [Romney] before he has the chance to define himself,” said the always astute Chuck Todd, NBC News’ political director, during his program Monday and just after the president’s campaign had issued a two-minute video press release about Romney’s dealings at Bain Capital.

One of the nation’s most respected political reporters, the Washington Post’s Dan Balz, echoed that view when he wrote in Wednesday’s Post, “There is no mystery to the [Obama campaign] strategy underway: define Romney before he can fully pivot to general-election voters after a nomination battle that went on longer than expected …”

Romney may well have failed to define himself as he would have liked to at this point, and that certainly is something his campaign needs to address. But I’m skeptical that it’s fatal. I’m not even certain the Republican nominee “needs to define himself quickly.”

Don’t get me wrong. The “define your opponent before he can define himself” argument is a compelling one when it comes to House races, low-visibility contests or even statewide contests when one of the candidates may not have the cash to compete. Voters usually don’t prefer candidates with a lot of negative baggage (though in the past three elections they have elected some “change” candidates with considerable personal baggage).

But presidential contests are different.

Unlike most elections in this country, by the end of the campaign, most voters are going to have watched Romney and President Barack Obama repeatedly, including in three live presidential debates that will draw tens of millions of viewers.

Those viewers will come to know the candidates (or believe that they know the candidates) and draw their own conclusions and assessments.

Obviously, a candidate can’t ignore how his opponent defines him. Ads and messages in the free media create impressions with voters — impressions that a damaged candidate must try to change. Because it’s easier to create impressions than to change them, Romney can’t simply give his opponents a free hand in defining him.

But unlike Sen. John Kerry, who ignored attacks on his military record during his 2004 presidential campaign, Romney’s campaign has already demonstrated that it won’t hesitate to answer attacks. And the former Massachusetts governor certainly will have the time and resources to define himself (including at his party’s national convention) and to address the caricatures being drawn of him by his opponents. He need not panic.

Because he accepted public campaign funds, GOP nominee Bob Dole lacked resources over the summer of 1996 to respond to President Bill Clinton’s attacks, and that allowed the Democrats to define for voters the election’s alternatives even before the Republican convention formally nominated Dole.

But Dole had another problem in that race, which was even more difficult to overcome than his cash-starved campaign: Clinton was popular and largely successful.

The unemployment rate in 1996 was 5.4 percent, down from 7.5 percent, when Clinton won the White House. And the president’s job approval, according to Gallup, remained in the mid- and upper 50s throughout the year. Clinton was in an ideal position to seek re-election and a far stronger position than Obama now finds himself.

Clearly, Romney will need to cross some threshold of acceptability as a potential president. Voters aren’t going to send just anyone to the White House. But when November rolls around, the question of who Romney is might not be nearly as important to voters as how well Obama has done.

In other words, if November brings a “choice election,” then the details of who Romney is will matter a great deal. But if voters decide that the crucial question is whether the president deserves a second term — if they see November as a referendum on the president’s performance during the past four years — then Romney is simply less important in the calculation, as long as he crosses that threshold of acceptability.

Of course, if voters ultimately do regard the election as “choice,” that automatically means that they are not so dissatisfied with Obama that they are actively looking for a reason to fire him. And in that case, it might not matter a great deal what they think of Romney. They are likely to vote to re-elect the president.

For now, the president remains in considerable trouble. And with economic clouds on the horizon here and in Europe, those re-election troubles could grow.

Stuart Rothenberg is editor of the Rothenberg Political Report.