As the candidates make their final pitch in a group forum before the first voters go to the polls in Iowa in less than three weeks, the GOP candidates have made their policy cases. Now, it's a question of whether they can win, and if they do, whether they have the skills to be the leader of the free world.

Gingrich's performance is being closely watched as he surges to the top of the pack in the field -- and faces questions about whether he is conservative enough for the GOP base.

He says yes -- and points to a 90 percent conservative voting record while a member of Congress, including four years as speaker of the House. But opponent Rick Santorum hit back, saying he faced a "conservative revolution" from within his own ranks while he was speaker.

The former speaker was also challenged on his taking $1.6 million from mortgage giant Freddie Mac after he left office. Gingrich said he did no lobbying, after Minnesota Rep. Michele Bachmann claimed that at that price, there's little difference between the technical definition of lobbying and "influence peddling."

Gingrich also defended government-sponsored enterprises, saying that they aren't all bad.

"I'm not going to step back from the idea that, in fact, we should have as a goal helping as many Americans as possible be capable of buying homes," he said. "There are a lot of government sponsored enterprises that are awfully important and do an awfully good job."

But while Gingrich kept up his game throughout the debate, his opponents also offered their arguments for why they should earn the nomination to defeat Obama. Mitt Romney, the former Massachusetts governor and venture capitalist, said he'll have credibility on the economy where Obama doesn't.

Romney said when it comes to debating the president on getting business to succeed and the economy on track, he will merely point to Obama's record as a CEO of sorts.

"How did you do when you were running General Motors," Romney said he would ask Obama, referring to the president's decision to offer billions in government loans, and close dealerships and factories in order to keep the automaker from going into bankruptcy.

"We have a president who, again, doesn't understand how the economy works," said Romney, adding that Obama has tried to pick winners in the energy sector.

"Not every business succeeds. ... In the real world, some things don't make it," he said.

Texas Rep. Ron Paul pointed to his penchant to defend civil liberties and refusal to allow the U.S. to be the policeman of the world.

"I don't want to police individual activities or lifestyle, and I don't want to run the economy," Paul said.

Texas Gov. Rick Perry said he's the Tim Tebow of the political world. As the Denver Broncos quarterback defies the odds, his record in job creation has also blown past expectations.

Utah Gov. Jon Huntsman, insisting that he, in fact, was a steadier conservative than any of the others on stage, but one who won't "contort himself into a pretzel" to meet definitions, simply said, "We're getting screwed as Americans."

In the free-wheeling and rapid debate, the candidates talked debt, leadership style and what they described as the president's shortcomings.

They also hit on foreign and energy policy as well as the judiciary. Former George W. Bush Attorneys General Michael Mukasey and Alberto Gonzales criticized a 28-page plan by Gingrich to reform the judiciary, including proposals to require judges to explain themselves to Congress as well as possibly get booted for bad decisions.

Called "dangerous," "ridiculous," and "outrageous" by the attorneys general, Gingrich asked whether they questioned Thomas Jefferson's decision to abolish 18 of 35 federal judges, and defended it by asking Jefferson's question: "Is the Supreme Court supreme? That is absurd, that would be an oligarchy."

Gingrich also said the Bush officials were "behaving exactly like law schools" but Americans can't let them "over-dictate to the rest of us."

Gingrich found support for his arguments from Romney and Bachmann

"Where it needs to end is under the Constitution of the United States," Bachmann said of judicial interpretation and the courts' predilection toward making activist decisions.

Bachmann also blamed Congress and the president for having "failed to take their authority." She said that Iowans in particular have demonstrated how to make judicial oversight work since they recalled three judges who ruled to allow same-sex marriage in the state against voter will.

"If we give to the courts the right to make law, then the people will have lost their representation. They need hold to their representation, That's why I commend Iowans, because they chose not to retain three judges decided that marriage would be in their likeness," she said.

On foreign policy, Bachmann sparred with Paul's laissez-faire approach to Iran, saying that she has "never heard a more dangerous answer" than Paul, who rejected a U.N. agency's report that Iran had returned to pursuing nuclear weapons after the program was declared dead in 2007.

Rather than focus on his primary foes, Romney slammed Obama, who recently requested from Iran that it return an unmanned spy drone that went astray and was captured by the Iranians.

"Timidity and weakness invite aggression on the part of other people," Romney said. "This is a president, the spy drone being brought down, he says 'pretty please?' A foreign policy based on pretty please? You got to be kidding."

The options are to destroy or go get the drone, added Perry. Instead, Obama "took a third route, which is the worst and the weakest, and that is to do nothing."

As for foreign policy closer to home, Perry and Santorum agreed they'd ask their attorney general to resign if he didn't know about Operation Fast and Furious, the botched gun-running program under the Obama administration that resulted in guns reaching Mexican drug cartels.

While the debate was full of attacks and counterattacks, the candidates said they were not violating Reagan's 11th Commandment -- to not attack fellow Republicans. Most of the candidates said they can take it, and dish it out. Romney said he'd reserve his biggest criticism for Obama. Paul said it was the job of the candidates to point out nuances and mistakes from their opponents that the media miss.

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