Updated

Newt Gingrich is the "king of K Street" and Mitt Romney is the "big-government candidate" in the Republican presidential primary race, says Michele Bachmann, whose pointed and laser-like attacks on the front-runners mark the latest effort by the primary candidates to take down their rivals.

With just over three weeks until the first nominating contest, Bachmann -- as well as other contenders, Ron Paul, Rick Perry, Rick Santorum and Jon Huntsman -- are vying to get a leg up over Gingrich, who has taken the recent lead in polling, and Romney, who has cast himself as the de facto nominee to challenge President Obama when all is said and done.

And with the clock ticking before the early voting begins, the candidates have sharpened their tongues and targeted the top-tier in a way that has largely been avoided until recently.

"We know that (Gingrich) has taken over $100 million. His offices are on the Rodeo Drive of Washington called K Street. He's the king of K Street," the Minnesota congresswoman said.

"And so for a person who has been influence peddling for over 30 years in Washington, D.C., to think that Newt Gingrich is somehow an outsider, when he's the consummate establishment insider, he's the big government candidate just like Mitt Romney is the big government candidate, that's not what we want in our nominee. It doesn't even survive the falling off the chair laughing test," Bachmann continued.

"I think they come from the same mold. They're about the same. They're both on the defensive. They're both explaining themselves," said Paul, who has tied Romney in some polling, including in the first-caucusing state of Iowa. Another debate -- hosted by Fox News -- will be held Thursday night in The Hawkeye State.

"They're not consistent. I think they more or less admitted that. They've changed their positions on it. It's not that they're in denial. It's just that they admit that they were on one side of the position here, and on the other side of a position on another time," said the Texas lawmaker.

Paul points to Gingrich's taking $1.6 million to advise Freddie Mac, a government-sponsored enterprise whose practices are largely blamed for the collapse of the housing market, as evidence that he is neither conservative nor principled. Gingrich says his work for Freddie Mac was that by a private citizen as a strategic adviser.

But Paul calls the payday "immoral."

"I wouldn't have taken their money. You know, just for the fact that I think it was an immoral thing to take money. Besides I don't like this idea that you're going to influence somebody that is a pseudo-government agency," Paul said.

Bachmann said both Gingrich and Romney, whom she morphed into a single candidate "Newt Romney," supported some kind of health care mandate. She added that they both have agreed at some point with the administration on cap-and-trade, they both supported the $700 billion bailout, illegal immigration and the payroll tax, which she noted has shown no evidence of its job-creating ability.

"It is very clear that there's not a dime's worth of difference between the two of them," she said. "So when you take a look, and people say this is a two-man race, I would agree. But the one man is Newt Romney and the other man is Michele Bachmann, the only proven consistent constitutional conservative."

Rick Santorum, who as a former Pennsylvania congressman helped shepherd the Republican Revolution of 1994 before becoming a senator, said Gingrich has done well at the debates because "his forte is glib." But he questioned whether his leadership style -- which takes on the form of a "professor-teacher mentality" -- will bear itself out.

"If you look at the leadership difference between the two of us, you know I was able to lead and successfully get a lot of things done when I was in Washington, D.C., and had the respect of my colleagues, was elected to leadership positions. And I think Newt had, let's say, a much more difficult path once he was in leadership," Santorum said.

Santorum also said that during Saturday night's debate, Romney and Gingrich "were back and forth" on core issues, including the bank bailout, cap-and-trade and the individual mandate.

As for Perry, he called Romney "out of touch" with the average Iowan.

Huntsman also used the Sunday talk-show circuit to challenge the pack. The former Utah governor and ambassador to China, who was not invited to attend Saturday's debate, said he's getting "whiplashed" from all the ups and downs in the GOP race.

With the latest polls showing Gingrich surging in Iowa, South Carolina and Florida, three of the four first nominating states, and Romney holding a big lead in New Hampshire, the other January race, all of the candidates claim they still have time to rise in the polls -- or perhaps pull down the leader board.

"The voters will begin to coalesce around a candidate about a week to 10 days out. The marketplace is still open. People are shopping. They are listening very, very carefully," said Huntsman.

"We've had people, you know, leading the pack off and on this whole past year, so it will be interesting to see just what happens in the next week or two," Paul said.

"It is, believe it or not, still early. I mean, there's still three weeks left even before Iowa. A lot of information is yet to disseminate out," said Santorum.

"I intend to be the nominee. I'm not giving up. I fully intend to be the nominee of our party," Bachmann said.