Mitt Romney has the opportunity to all but lock up the nomination with wins in a batch of Super Tuesday states today. He is now leading in most polls in Ohio and is expected to cruise to easy wins in Vermont, Massachusetts, North Dakota and Idaho. It is even possible he may take Tennessee. That would leave Georgia to Newt Gingrich, Alaska to Rep. Ron Paul (R-Tex.) and Oklahoma to the struggling Rick Santorum.

But it is clear that Ohio is at the center of Romney’ effort to put the race away. He was there all day on Monday, making his final case on a focused economic message. In Canton he told the crowd: “I see a lot of folks all talking about lots of things. But what we need to talk about to defeat Barack Obama is getting good jobs and scaling down the size of government.” Given Santorum’s failure to qualify for a full slate of delegates, Romney zeroed in on his opponent’s error. As Politico reported, “With stops here, in Canton and a planned evening rally in Zanesville, Romney on Monday hit cities in congressional districts where rival Rick Santorum failed to submit full delegate slates for Tuesday’s Ohio primary.”

Santorum isn’t waiting for the ballots to be counted before spinning the results. His senior adviser is already trying to say losses in key races don’t matter, whining once again about the money his opponent is using to roll over him:

Despite the snide confidence of Santorum’s flack, it will be impossible for Santorum to pretend Romney isn’t the front-runner if he wins most of the races today. A Romney adviser wasn’t impressed with the spin. He cracked to me last night, “Santorum has made a practice of spinning his losses, be they debates or states. Now he is expanding the practice to a pre-spin of why he will lose. I guess they wanted to get ahead of this process.”

If the races play out as expected, the race in retrospect would take on a different complexion. The triple wins for Santorum on Missouri, Minnesota and Colorado on Feb. 28 would then be an aberration in states with high concentrations of religious conservatives and where turnout was low and Romney put forth limited effort. Romney’s march to the nomination would look more like a relatively strong effort with comparatively few losses than the serial failure of a “weak” candidate to connect with the base.

And, in fact, with the advantage of hindsight, we can see that much of the analysis and pundits’ tropes look silly. Romney didn’t have a “25 percent cap” on support, as many pundits repeated. He wasn’t unable to win the base; it simply took a while. His “too negative” campaign turns out to have produced voluminous and very conservative policies on taxes, spending, jobs, entitlements and national security. And the candidate who seemed too stiff or genteel to win in a street fight took out a series of contenders with methodical ruthlessness. The more his opponents complained about the attacks, the more it seemed that he had the kind of steel spine needed to stand up to the Obama attack machine. And he did this while a conservative media overwhelmingly rooted for each and every rival, only reluctantly vetting them or daring to criticize.

The primary process isn’t over. But if Romney comes out of Super Tuesday with the lion’s share of the votes, he’ll be the presumptive nominee. The race already has had the familiar impact on the front-runner: He looks more confident and, yes, more presidential than his opponents. He has big challenges ahead that include unifying the GOP, focusing his economic message in a way that accounts for positive developments in the economy and making the case that on everything from Iran to the debt to entitlement reform Obama has shrunk from the challenges of the day.

Still, those who consider the GOP’s goose already cooked should perk up. We are months before the election. Unemployment is still high, the debt ceiling is likely to be reached again and Obama is essentially trying to run out the clock by doing nothing this year. He has plenty of vulnerabilities. I share my colleague Michael Gerson’s take that “confident predictions of Romney’s defeat are not only premature. They are seriously frivolous.”

While conservatives (many of whom rooted against Romney throughout) like to dwell on his weaknesses, in their more lucid moments they also recognize that Obama of 2012 is not the Obama of 2008 who needed to present a blank slate to the public, capi­tal­ize on a financial meltdown and merely stand thoughtfully while his opponent ran around breathlessly (shutting down and starting up his campaign was truly a low point, you may recall in the McCain follies). This time around, voters know he’s a liberal; it is he who must defend a shaky economic record, and his opponent will appear forceful, calm and entirely credible as a replacement. Throw in an exciting VP pick and the Romney-Christie or Romney-Rubio ticket looks solid.

And if Romney’s take down of Santorum in the last debate or his willingness to open up about his personal life is any indication, he is a candidate who can learn and adjust. He should not be underestimated.