Former House Speaker Newt Gingrich’s convincing win in the South Carolina primary race is still sinking into the collective political consciousness but there are already a few lessons we’ve learned from the vote.

COLUMBIA, SC - JANUARY 21: The image of Republican presidential candidate, former Speaker of the House Newt Gingrich is projected on a screen at a primary night rally as he is announced as the winner of the South Carolina primary January 21, 2012 in Columbia, South Carolina. (Photo by Mark Wilson/Getty Images)

Here’s five:

1. Debates matter. A lot.: Fifty-two percent of the South Carolina primary electorate said that the recent debates were one of the most important factors in deciding their vote. Of that group, Gingrich beat Romney 47 percent to 24 percent.

What those numbers make clear — again — is that the debates have been the defining trait of this race, eclipsing early state organizations, fundraising and television ads.

The two debates over the past weeks gave Gingrich a foothold to climb back into a race that without them, he would have had no ability to match Romney — in organization or money spent.

(Sidebar: Imagine if Romney had taken a pass on the two debates this past week? Sure, he would have taken some heat. But would it be worse than the press hit he is going to take following Gingrich’s win?)

The stark reality of how in­cred­ibly important the debates are in this race make the NBC set-to on Monday night and CNN’s on Thursday even more important. Romney has to perform better in them than he did in the last two or run the risk of watching a similar pattern play out in Florida.

2. It’s a marathon, not a sprint: If Romney had won South Carolina, the race for the Republican presidential nomination would have almost certainly been over. Romney would have won the last two contests (New Hampshire and South Carolina) and would have been a big favorite heading into Florida in 10 days.

But, he didn’t. And that means we are in for — at least — another six weeks of campaigning, all the way through the March 6 Super Tuesday vote if not further. (South Carolina is functioning as a sort of political Groundhog Day.)

Romney remains a favorite in Florida — the state is much more dependent on ad campaigns and organization — and is likely to win Nevada on Feb. 4. He also retains an edge in Arizona, due to its large Mormon population, and in Michigan, the state in which he was born.

Super Tuesday, when 10 states including Ohio and Virginia are scheduled to vote, then must be the place where Gingrich makes his stand. Whether he can raise the millions and build the organizations he will need in these states remain to be seen. But, Gingrich’s win tonight means he will have a chance to prove that he can.

Get ready, it’s going to be a long(ish) one.

3. Frontrunners falter: It’s hard to remember a presidential primary fight in recent memory where the perceived frontrunner didn’t look very vulnerable at one point.

Barack Obama lost New Hampshire to Hillary Clinton in 2008. George W. Bush lost (badly) in New Hampshire to John McCain in 2000. Bob Dole lost the 1996 New Hampshire primary to Pat Buchanan.

At the start of this week, Romney looked like he might not get his uniform dirty — yes, the Fix is looking forward to the NFL playoffs tomorrow — in his sprint to the nomination. (Mixed sports metaphor alert!)

Then came the two debates, the news that he had actually lost the Iowa caucuses to former Pennsylvania senator Rick Santorum and tonight’s defeat at the hand of Gingrich.

That makes the next ten days — between now and Florida — the most trying of the period of his campaign. The Romney campaign has long asserted, privately, that they expected him to face a serious challenge at some point in the race.

But, knowing that the valley was coming and seeing your way through it to the other side are two different things.

4. Mitt Romney has a base problem: In some ways, we are back to where we thought we might be in this race. Romney is the clear choice of the Republican party establishment but he simply cannot close the deal with conservatives — particularly evangelical voters — who seem willing to support anyone other than Romney.

In South Carolina, two-thirds of the primary electorate identified themselves as evangelicals. Among that group, Gingrich took 44 percent to 21 percent for Romney. Sixty four percent of the South Carolina electorate identified themselves as supporters of the tea party movement; Gingrich beat Romney 45 percent to 25 percent among that voting bloc.

Romney and his team made a calculated decision in this race not to try to paint him as the socially conservative candidate — a positioning that failed and failed badly in 2008.

The question now is whether they stick to the script — focus on President Obama’s weaknesses and Romney’s profile as the person best equipped to beat Obama — or pivot in some meaningful way.

Our guess? Romney knows he can’t convince conservatives/tea party types that he is one of them. What he has to do instead is convince them that Gingrich isn’t one of them either.

That effort began with Romney’s concession speech in South Carolina in which he painted the race going forward as between someone who knows the private sector and believes in free markets and someone who knows the government and doesn’t. “Our campaign will be about the business I helped to start, not the bills I helped to pass,” said Romney.

Which leads us to....

5. It’s going to get real nasty, real quick: Yes, South Carolina has the reputation of being the home of negative campaigning. But, the Palmetto State primary was, by historical standards, decidedly tame.

To quote Carl Spackler (aka Bill Murray in “Caddyshack”): “The kidding around is pretty much over.”

The 10 days between now and the Florida primary will be something like the three weeks between New Hampshire and South Carolina during the 2000 primary when George W. Bush and his allies took the fight to McCain in a remarkably aggressive way. (Worth noting: it worked for Bush as he won South Carolina and, eventually, the Republican nomination.)

Romney has millions of dollars — $19 million, to be exact — to spend. Restore Our Future, the Romney-aligned super PAC, has million more. And all of that will be spent on an effort to destroy Gingrich and stop his momentum coming out of South Carolina.

If he’s able to, Gingrich and his super PAC — Winning the Future — will respond in kind. But will Gingrich be able to raise the sort of money he needs to fight Romney to the political death in Florida?

In short: If you hate negative campaigning, you may want to turn your television off for the next few weeks. Or maybe months.