Arizona Republican Presidential Debate 2012: Grading the Candidates
Rick Santorum and Mitt Romney dueled at CNN's Republican debate Wednesday night in Mesa, Ariz., but Romney emerged on top at what will likely be the final debate ahead of the primaries. Reuters

Rick Santorum and Mitt Romney duked it out at CNN's Arizona Republican debate Wednesday night, but Romney came out on top at what will likely be the final debate of the primary season.

Santorum, Romney, former House speaker Newt Gingrich and Texas congressman Ron Paul fielded questions from John King on a range of topics including birth control, Iran and immigration. It was the last chance for the candidates to woo Republican voters ahead of the Arizona and Michigan primaries next Tuesday, as well as the multiple contests on Super Tuesday, March 6, and beyond.

Much of the debate was focused on Santorum, a former senator from Pennsylvania, and Romney, an ex-Massachusetts governor, who currently top national polls and are competing for front-runner status. Wednesday night, Santorum was repeatedly hit with difficult questions about his history with spending earmarks from his time in the Senate, raising the U.S. government's debt limit, and other issues that opponents have cited as evidence that he isn't a true fiscal conservative.

Gingrich, usually electric on the stage, had a relatively average performance. While Paul was consistent and didn't stumble for a second, his stance on Iran will make it hard for him to appeal to many conservative voters.

Here's a rundown of the winners and losers from Wednesday night's debate.

SANTORUM: D

All eyes were on the Pennsylvanian, who has been surging ahead of Romney in national polls this week. According to averages calculated by Real Clear Politics, Santorum was the favorite candidate of 33.7 percent of GOP voters, while Romney was the top pick of 28.4 percent.

But Santorum had too many moments of weakness. One that stood out was when Santorum explained why he supported President George W. Bush's No Child Left Behind legislation.

It was against the principles I believed in, but sometimes I take one for the team. I made a mistake, Santorum said. Sometimes politics is a team sport.

The comment made Santorum look less like a strong leader and more like a member of the insider culture that the presidential candidates often condemn. Paul was the only Republican on stage to slam the Pennsylvania conservative on the comment, saying that's what the problem is with Washington.

As the two current leaders in the race, much of the debate was a bickering back-and-forth between Santorum and Romney, but it was the latter who instigated most of the attacks. When discussing the debt ceiling, Romney accused Santorum of being a big spender. Voting for the debt ceiling five different times without voting for compensating cuts. Voting to fund Planned Parenthood, voting to expand the Department of Education. During his term in the Senate spending grew by some 80% of the federal government, Romney said.

In response, Santorum accused his chief party rival of adopting the Occupy Wall Street rhetoric for planning to tax the 1 percent, which Romney claimed was untrue.

The two also had a lengthy and muddled conversation about earmarks, which the Romney campaign has criticized Santorum for supporting in the past. As Romney accused his rival of excessive spending, Santorum spent a decent amount of time defending the process of federal set-asides to support local projects and accused Romney of doing the same thing to get money for the Salt Lake City Olympics in 2002.

While I was fighting to save the Olympics, you were fighting to save the Bridge to Nowhere, Romney snapped back.

Santorum had a few of strong jabs at Romney, but he seemed nervous at times and his tone was overall much more defensive than offensive. This debate was a chance to further his momentum into the Michigan and Arizona primaries next Tuesday, as well as the Super Tuesday and upcoming contests in March, but the Pennsylvania Republican fell flat.

There was also anticipation about how Santorum would defend controversial comments that dogged him on the trail all week, including a 2008 speech in which he had claimed Satan was threatening America, but debate moderator John King did not bring that up.

Memorable Quotes:

I have to admit, I voted for that, it was against the principles I believed in, but you know, when you're part of the team, sometimes you take one for the team, for the leader, and I made a mistake. You know, politics is a team sport, folks.

Find out what Joe Biden's position is [on foreign policy] and do the opposite you'll be right 100 percent of the time.

ROMNEY: A

Romney is a winner because he managed to stay on top of Santorum. That was an important goal for the former Massachusetts governor Wednesday night, as Santorum is his currently his biggest competition.

Romney did lose an opportunity at the end of the debate, when King asked him what he though was the public's greatest misconception about him. Romney could have mentioned something about how more conservative voters complain he is too moderate, like he pounded over and over in his CPAC speech, or even challenged the notion that he was not relatable to regular Americans. Instead, he completely did not answer the question. When King called him out, he said, You get to ask the questions you want--I get to give the answers I want.

Two interesting moments worth noting: the Massachusetts governor made a Seinfeld reference at the beginning of the debate (see below) when the audience started to applaud during his introduction. Also, the GOP presidential hopeful referred to his own Massachusetts health care legislation as Romneycare, a term favored by his political rivals who compare his plan with Obama's.

Memorable Quotes:

As George Costanza would say, when they're applauding, stop.

Let's not forget that four years ago, long after Romneycare was put in place, four years ago you not only endorsed me, you went on Laura Ingraham and said this is a guy who is really conservative and we can trust him.

PAUL: A-

Paul isn't interested in winning the primaries in Michigan, Arizona or other states in March. The Texas libertarian, who CNN dubbed the delegate hunter at the outset of the debate, plans to assemble as many delegates as possible as the race goes on. Therefore, his primary goal in the debate was to maintain consistency on his stances.

Consistent was the word Paul chose to describe himself when prompted by King and he certainly was. Paul stood out for having the most memorable soundbites on birth control and war, spicing up what was a relatively dull debate.

One thing that likely won't sit well with many Republican voters was Paul's relaxed stance on Iran, although he has always made his position clear. He drew a few boos from the audience when he said there was no proof that the Middle Eastern country had nuclear weapons.

It's risky and reckless, but if you're so determined to go to war, the only thing I plead with you is, do it properly, Paul said, adding that the president should ask the people and consult with Congress before taking such action.

Memorable Quotes:

Because he's fake (in response to a question about an attack ad that called Santorum a fake conservative. Santorum responded by saying I'm real, I'm real and pointing to his skin.

This is war, people are going to die.

On how birth control is like gun control: Guns don't kill people, criminals kill people. ... It's the morality of society we have to deal with.

The biggest misconception about me is the misconception by the media that I can't win.

GINGRICH: C

The former speaker's run for the party nomination has been a roller-coaster ride, and he's now experiencing a low. Wednesday night's debate was a chance to stand out during a campaign tradition that has shown to be his strength, continuing to be charismatic, witty and brainy.

Gingrich didn't necessarily disappoint this time around. Although he didn't get as much attention as Santorum and Romney, he made a number of sweeping attacks at President Obama. Gingrich could have done a better job, however, if he had engaged the candidates more. For someone who usually has stellar debate performances, this one was average for him.

Memorable Quotes:

I'm inclined to believe dictators, I think it's dangerous not to.

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