TAMPA -- Say goodbye to Mr. Nice Guy Mitt.

Mitt Romney on Monday night came with verbal knives for newly minted frontrunner Newt Gingrich. Foreshadowing the tone of Republican races in Florida, Romney was negative all day.

And he drew blood.

More significantly, Romney drew silence at the Tampa debate.

The voluble former House Speaker seemed able to speak about anything in the past 18 debates. But he was at a loss for words after Romney called him a lobbyist, an “influence peddler,” and suggested that Gingrich was no “historian” when it came to his high-priced consulting contract with federally backed lender Freddie Mac.

“They don’t pay people $25,000 a month for six years as historians. That adds up to about $1.6 million,” Romney said. “They weren’t hiring you as an historian. And this contract proves that you were not an historian. You were a consultant.”

Gingrich had only four words of response: “I was a consultant.”

The two went back and forth, interrupting each other. Gingrich tried to bring up Bain Capital, Romney’s venture-capital firm that had profited at times from laying off workers and closing factories.

But Romney kept coming: “another area of influence-peddling…”

Gingrich stopped gesticulating. He froze for a second. He had to calm it down, slow it down. He was losing. He placed his hands on the podium.

“No, not — now, let me be very clear, because I understand your technique,” Gingrich said, mentioning how Romney had attacked the records of his opponents in the 2008 presidential race.

“It’s unfortunate,” he said, “and it’s not going to work very well, because the American people see through it.”

But it does work.

Going negative works. Just ask Gov. Rick Scott. Ask former Gov. Charlie Crist. Ask former Sen. Mel Martinez. In Republican primaries, they ate their opponents alive — with Scott and Martinez running particularly negative races against the same politician, Bill McCollum, who just happens to be a co-chair of Gingrich’s Florida campaign.

Not only did Gingrich have a rare, quiet moment. The crowd was pretty silent, too. In South Carolina, the roaring crowd was such a boon to Gingrich that he plans to run clips of the debate as ads in Florida. No extra music. Just the crowd cheering. After turning questions about his failed marriage or his comments about food stamps into criticisms of the news media, Gingrich had the South Carolina crowd in his hands in two debates.

Gingrich didn’t have those moments on Monday. He lost the expectations game, which Romney won just as he was losing in the Florida polls. The other candidates, Rick Santorum and Ron Paul, trail badly in the polls and got less airtime in the debate.

"It’s different when there’s not a game-show like environment," said Stuart Stevens, top strategist for Romney, noting that the audience wasn’t "hooting and hollering" and "doing the wave" for Gingrich.

Romney didn’t just pummel Gingrich on stage. He’ll be doing the same in your living room. On Monday, he announced he’s spending about $2 million on 30-second spots telling Floridians that, while they lost their homes, Gingrich was enriched by Freddie Mac.

Coupled with Monday night’s debate clips that will be endlessly looped on cable-news shows, the sustained negative assault by Romney will likely make a difference. How much is anyone’s guess.In Iowa, negative ads tore up Gingrich and helped cost him the election. In South Carolina, Gingrich went on the attack and whipped Romney, who tried to seem above the fray and tried to stump against President Barack Obama.

On Monday night, a different Romney appeared. This wasn’t the guy who stood on stage in South Carolina and expressed regret for bashing his fellow Republicans too often.

After that debate, which Gingrich clearly won, he whipped Romney in South Carolina by about 12 percentage points. Gingrich was tough. Romney wasn’t.

In Florida, Romney came out swinging.

“The Speaker — when I was fighting against cap and trade, the Speaker was sitting down with Nancy Pelosi on a sofa encouraging it,” Romney said. “When I was fighting to say that the Paul Ryan plan to solve Medicare was bold and right, he was saying that it was right-wing social engineering.”

On three occasions in the first five minutes, Romney said Gingrich was “disgraced” by his fellow Republicans who ousted him from his speakership by 2008.

Gingrich didn’t have much of a response.

“Well, look, I’m not going to spend the evening trying to chase Governor Romney’s misinformation. We’ll have a site at Newt.org by tomorrow morning,” Gingrich said. “I just think this is the worst kind of trivial politics.”

But it’s that type of campaigning that often wins elections in Florida’s Republican primaries.