Editor's note: David Gergen is a senior political analyst for CNN and has been an adviser to four presidents. He is a professor of public service and director of the Center for Public Leadership at Harvard University's Kennedy School of Government. Follow him on Twitter: @David_Gergen.
(CNN) -- If our politics weren't so fluid and volatile, one would think, now that the votes are tallied in New Hampshire, that the race for the Republican nomination is virtually over. But for better and worse, we are living in a new era.
By any standard, Mitt Romney has now achieved some impressive results:
-- He is the only GOP candidate other than Jerry Ford to win back-to-back victories in Iowa and New Hampshire (and of course Ford was a sitting president).
-- In a crowded field in New Hampshire, he shattered the 25% ceiling that was dogging his candidacy. His nearly 40% total of the vote beat John McCain's victory total four years ago.
-- He delivered a speech after his New Hampshire victory that was carefully crafted for prime time and was his best of the year -- far better than his forgettable performance after Iowa. The campaign has also started to draw more upon the warmth and vibrance of Ann Romney, a substantial asset for her husband.
-- And he has also managed to execute a divide-and-conquer strategy well enough that no single rival has emerged who can unite the anti-Romney forces.
So, by the normal rules of politics, Romney holds a commanding position heading into the next primary on the docket, coming up in South Carolina on January 21. Someone has to beat him there or it's game over.
But -- and this may be a significant but -- there is a new wild card in play: a PAC supporting Newt Gingrich allegedly has enough money and enough buys to pour in $3.5 million worth of negative advertising against Romney in the next 10 days. As their blood feud heats up, the Gingrich forces clearly hope to destroy Romney as effectively as they believe the Romney PAC destroyed Gingrich with a barrage of negative advertising in Iowa.
Can a huge block of ads in a small media market, trashing Romney as a predatory buyout tycoon, do to Romney what the candidates haven't been able to do on their own -- bring him down?
Democrats have all along believed that they can make the charge stick, just as Ted Kennedy did when Romney challenged him for the Senate in 1994. They have already started to track down disgruntled former employees, and their files are presumably bulging with new stories.
Meanwhile, Republican rivals like Gingrich and Rick Perry (who has taken to calling Romney a "vulture capitalist") may think they have knocked Romney back on his heels with their assaults heading into the New Hampshire vote. Romney was rattled on the stump, making a couple of gaffes and telling small fibs that may haunt him down the road. (And Gingrich is starting to go after Romney on social issues such as abortion.) So, with South Carolina as make-or-break, the men behind Gingrich have drawn their daggers.
But there is an old and time-tested adage: When you strike a king, you must kill him. It is not at all clear that Romney's rivals have that capacity, and there is a growing possibility that Romney could not only block them, but could thrust a sword into them in return.
For starters, the assaults against Romney had no visible impact on his vote in New Hampshire. Sure, they came late enough in the game that most voters didn't have a full grasp -- but even so, they bounced off. And while South Carolina has a lousy unemployment problem with a lot of jobs shipped overseas, it is also a business-friendly state, especially in the Greenville-Spartanburg area in the northwest, where international companies have built plants along the "I-85 autobahn." South Carolinians are pretty sophisticated about "gales of creative destruction." And Romney -- unlike Gingrich in Iowa -- has money to spend on ads countering the attacks, which is important for creating a shield against the daggers.
Also, a backlash against Gingrich and Perry has sprung up among conservative economists, who reject the premise behind the attacks and are outraged that Republicans who have pledged fealty to free-market principles are now trying to sabotage a successful entrepreneur for political gain. Leave that to the Obama Democrats, they seethe.
Finally, Romney showed evidence Tuesday night in his acceptance address that he is more than willing to fight back -- indeed, he showed that he wants to flip the argument against them so that he emerges as the candidate who is the champion of the free market against those who would cripple its vitality.
My own sense is that, absent more damning evidence, Romney can seize the high ground in this fight, certainly among GOP primary voters. His leadership at Bain Capital has always been a central premise of his campaign, and it has worked reasonably well, because Bain Capital has a positive reputation in Boston and beyond. I have worked with today's Bain partners on several projects, mostly revolving around nonprofits, and I have found them to be highly professional, socially committed individuals. Some are seen as among the leading philanthropists in New England.
It is worth remembering, too, that the Olympics hired Romney to head the Games while he was at Bain Capital. Is it logical to think the Olympic committee had any sense that Romney was a predatory capitalist? The question answers itself.
In short, attacks on Romney's business experience at Bain have become a wild card in the South Carolina race. Perhaps they will inflict serious damage and reshape the race. But it seems more likely that Romney will blunt the attacks and, in conservative eyes, turn himself into a more admired champion of free markets who has a better chance of uniting the party behind him. If he handles the issue with skill, he could even blunt the Democratic assaults that are surely coming.
The opinions expressed in this commentary are solely those of David Gergen.