Even as he made a last-ditch pitch to Iowa voters to back his “relentlessly positive” campaign, Newt Gingrich had already moved on to his next frontiers: New Hampshire, South Carolina, Florida — and Mitt Romney.

Pummeled by more than $3 million in negative ads, Gingrich was running a distant fourth in final results in Tuesday’s first-in-the-nation Iowa caucuses after insisting on staying positive, emphasizing his “Ronald Reagan conservatism” and touting his record as a House speaker who brought change to Washington.

Gingrich said his finish was remarkable given that he “survived the biggest onslaught in the history of the Iowa caucuses.” And he signaled his plans to march forward yet again: “This is going to be a debate that begins tomorrow morning in New Hampshire and will go on for a few months.”

Gingrich’s emphasis on his record changed abruptly even before the returns were in. He began calling Romney a liar, accusing the former Massachusetts governor not only of misrepresenting his moderate record but of dodging responsibility for a barrage of attack ads. Many were paid for by a super PAC supporting Romney.

Late in the day, Gingrich’s campaign released a copy of a full-page ad that will run Wednesday in the Union Leader, New Hampshire’s largest newspaper. Under the banner headline “The Choice,” the ad features pictures of Gingrich, a “Bold Reagan Conservative,” and Romney, a “Timid Massachusetts Moderate.”

Gingrich has been clear that he has no plans to concede before the Jan. 21 primary in South Carolina. However, whether he can find the momentum — and the money — to regain his footing after falling from first place since early December remains unclear.

“There’s nothing more dangerous than a politician with nothing left to lose,” said Alex Castellanos, a Republican strategist who supported Romney in 2008 but who has remained neutral this election season. “I think he’s going straight to New Hampshire, where Mitt Romney and Romneycare live, and I think he’s going to try to set the record straight.”

In addition to the newspaper ad, Gingrich said he will begin running contrast ads against Romney in New Hampshire and South Carolina. An independent super PAC supporting him, Winning Our Future, has similar plans, according to its spokesman, former Gingrich aide Rick Tyler.

But no such ads are on the air yet — and the New Hampshire primary is less than a week away, on Jan. 10. Similarly, Gingrich’s campaign boasted this week that he raised $9.6 million in the final quarter of 2011. But the campaign won’t say how much it cost to raise that sum or how much money it has in the bank.

Tyler said he didn’t know whether or when the PAC would launch TV ads in the states with upcoming primaries. He also wouldn’t say how much money the committee has. But he did say that “there’s definitely a shift afoot” in strategy.

“We’re getting money from true believers in America who don’t want to see a liberal northeastern establishment candidate be our nominee,” he said.

Two debates in New Hampshire — in the coming weekend — could play to Gingrich’s advantage; his performance in a series of debates over the past year helped propel him to the front of the pack.

He has indicated that he is eager to hit the ground quickly in New Hampshire. He planned to leave Iowa as soon as the returns were in, with another bus tour in New Hampshire launching early Wednesday.

In a midday interview on Fox News, Gingrich dismissed questions about advertising and his campaign’s resources.

“We’re just getting started,” he told reporters after a mini-town-hall at the Drake Restaurant overlooking the Mississippi River in Burlington. “Figuring out what the core contrast is for the next 30 days is the most important thing we’re doing right now. I’m less concerned about the first wave of ads than I am about getting the strategy right. I’m fairly convinced that we will have a strategy that Romney will find very hard to deal with.”

Gingrich was worlds more energetic Tuesday than he had been over the past few days, evidence of just how debilitated he had been by the flu he was fighting. He drew cheers at a caucus site in Cedar Falls, touting his “positive” campaign — but the reality was that the message had been drowned out by the attacks against him.

“Gingrich speaks so well — he can name so many names and facts,” said Gary Diercks, 70, a retiree who heard Gingrich speak at a coffee shop in Muscatine on Tuesday morning and who was still undecided then. “At my age, that’s astonishing. But I do believe that Newt has some baggage.”