COLUMBUS, OH -- Feathers were ruffled on Sesame Street on Tuesday when the Obama campaign launched a campaign ad starring Big Bird.

The new spot, which airs on cable networks, mocks Mitt Romney for saying during last week’s debate that he would cut public funding to the Public Broadcasting Service – even though he likes Big Bird.

But Sesame Workshop – the nonpartisan nonprofit behind Sesame Street – wasn’t pleased. In a statement, Sesame Workshop objected to the ad: “We have approved no campaign ads, and, as is our general practice, have requested that both campaigns remove Sesame Street characters and trademarks from their campaign materials.”  

The ad begins with an ominous voiceover listing the names of Wall Street criminals, including Bernie Madoff and Kenneth Lay. The deep, dramatic voice then says, “It’s not Wall Street you have to worry about; it’s Sesame Street.”

The camera then cuts to a shot of Big Bird sleeping.

President Barack Obama has seized on Romney’s Big Bird comment to argue that his Republican challenger would crack down on beloved American institutions such as Sesame Street but would allow Wall Street to run wild.

Speaking to a crowd of 15,000 in Columbus, OH the President said, “Today (Romney) decided we’re going after Big Bird. Elmo’s making a run for the border and Oscar is hiding out in a trash can.”

Emphasizing the Sesame Street theme, recording artist will-i-am kicked off his performance at the Ohio event by playing the Sesame Street theme song.  

The Obama campaign has also dispatched Big Bird mascots to stand outside Romney campaign events and even Michelle has entered the fray. On Tuesday, the first lady told supporters in Loudon, Va.: “We all know good and well that cutting Sesame Street is no way to balance a budget.”

Related: 'Sesame Street' wants Obama campaign to yank ad mentioning Big Bird

Speaking in Van Meter, Iowa, Romney fired back: “These are tough times with real serious issues. You have to scratch your head when the president spends the last week talking about saving Big Bird.”

The Romney campaign noted that Obama has in recent days made more public references to Big Bird than Libya – where the U.S. consulate was recently attacked and the ambassador killed. 

But the Obama campaign stands by its strategy.

“The point we’re making here is that when Mitt Romney was given the opportunity to lay out how he would address the deficit … his first offering was to cut funding to Big Bird and that is absurd and hard to take seriously,” Obama campaign spokeswoman Jen Psaki told reporters.

With polls showing Romney improving since the debate, it remains to be seen whether the president’s “Big Bird Offensive” will sway undecided voters.

But one thing is clear – Big Bird says the campaign ad doesn’t fly.

Steve Helber / AP

Republican presidential candidate former Massachusetts Gov. Mitt Romney and his running mate Rep. Paul Ryan, R-Wis., wave to supporters during a rally in Fishersville, Va., Oct. 4.

FISHERSVILLE, Va. – Capitalizing on momentum from Wednesday night's debate, Mitt Romney and Paul Ryan whipped up their base here in rural Virginia with a raucous rally complete with fireworks, live music and pointed new attack lines aimed at their Democratic opponents.

"I got the chance to ask the president questions that people across the country have wanted to ask him, such as why is it that he pushed Obamacare at a time when we had 23 million people out of work? I asked why is it that the middle class is still buried in this country – why is it we have 23 million people out of work?" Romney said, ticking off several more debate topics. "I asked him those questions and you – you heard his answers."

Romney wove highlights from the debate into his traditional stump speech, revisiting the showdown that was watched by 62 million Americans.

"What you didn't hear last night from the president is why it is the next four years are possibly going to be better than the last four years. He doesn't have a way to explain that, because he has the same policies for the next four years as he had for the last four years," Romney said. "He said go forward. I call it forewarned, all right?"

Ryan also weighed in on the debate for the first time, predictably praising the man at the top of the GOP ticket.

“Every now and then, we see a glimpse into the future. Last night, we saw a clear picture. We saw a clear choice," Ryan said. "Last night, America got to see the man I know: a leader, a decisive man, an optimistic man, a man with a plan to get people back to work and to protect our freedoms.”

Thursday's event showed a tilt back toward the Republican base. Country music star Trace Adkins warmed up the crowd with a 30-minute set, and the National Rifle Association officially bestowed its endorsement of the Romney/Ryan ticket.

“We stand on the edge of an Obama cliff with our freedom. If President Obama gets re-elected, he’s going to have one to three Supreme Court appointments," warned Wayne LaPierre, the NRA’s executive vice president.  "And I guarantee you this: If that happens – one to three more Sotomayors and Kagan – we can kiss our constitutional right to own a firearm in the United States goodbye along with a lot of the rest of our freedoms. And we can’t let that happen.”

Slideshow: On the campaign trail

Reuters, Getty Images

In the final push in the 2012 presidential election, candidates Mitt Romney and Barack Obama make their last appeals to voters.

Launch slideshow

With the first presidential debate out of the way, the focus turns to the vice presidential debate next Tuesday in Kentucky.

On Thursday, Romney and Ryan pounced on the vice president's statement earlier in the day that Democrats aimed to repeal the so-called Bush tax cuts for the wealthiest Americans.

“Last night President Obama made it very clear he’s going to raise taxes. Today, Vice President Joe Biden made it even more clear,” Ryan said. “In Iowa … he asked if he and President Obama wanted a trillion dollar tax hike and his response to himself was, ‘Yes we do.’ That’s a direct quote, friends. Well, Virginia – no, we don’t!”

Romney piled onto his running mate’s remarks: "The vice president blurted out the truth today. They plan on raising taxes on the American people, and that will kill jobs. We will not let that happen. We want to create jobs, not kill jobs in this country.”

Democrats cried foul at that and other comments by Romney touting his own tax plan and accusing the President of trying to raise taxes on middle class Americans.

"Clearly, Mitt Romney thinks facts don’t matter – but the hard-working Americans who he’d punish with his policies do,” said Obama campaign spokesperson Lis Smith, who accused Romney of a "streak of dishonesty."

As the weekend approaches, Romney continues to campaign in Virginia before heading to the battleground state of Florida, while Ryan continues to prep for the debate and raise money for the GOP ticket.

Updated 10:07 p.m.

Mitt Romney and Newt Gingrich, each battling furiously for a win in Saturday's South Carolina primary, pointedly questioned each other's experience to be president, while being forced to account for standing questions about the challenges they face to winning the nomination and beating President Obama.

The two leading candidates in South Carolina's primary this weekend largely avoided sniping at each other in the first half hour of the debate -- a spirited affair less than 36 hours before voting begins in the Palmetto State -- but engaged each other more directly as the evening progressed.

Gingrich was pressed to explain his past support for a mandate for individuals to purchase health insurance, and his manner of leadership as speaker of the House, a tenure described by critics as erratic.

But Gingrich scored early -- and decisively -- with a fiery response to allegations from an ex-wife that drew wild applause from the crowd in attendance.

Romney, meanwhile, had to defend his business record and answer questions as to why he wouldn't release his income tax records, all while relitigating conservative criticism of the health care reform he signed as governor of Massachusetts.

Through this, former Pennsylvania Sen. Rick Santorum, crowned the winner this morning of the Iowa Caucuses after a retabulation of results, was anxious to take on both Romney and Gingrich, distinguishing himself as a steady if not-flashy alternative to the two leading candidates.

The debate, the 17th of the cycle, followed one of the most dramatic days of the 2012 campaign. Thursday saw Texas Gov. Rick Perry’s exit from the campaign trail, new extramarital allegations against Gingrich, polling data showing Romney’s advantage slipping in South Carolina, and a new declaration by the Iowa GOP anointing former Santorum – not Romney – the winner of its Jan. 3 caucus after certifying official results.

Perry drops out of GOP presidential race, endorses Gingrich

The tone of the forum was set early when Gingrich angrily assailed CNN moderator John King for opening the debate by asking Gingrich to answer allegations made by his ex-wife, Marianne, in an interview with ABC News, saying the then-speaker of the House asked to engage in an "open marriage," or else he would file for divorce.

"I am appalled that you would begin a presidential debate with a topic like that," Gingrich said, earning wild applause from the audience. "To take an ex-wife and make it two days before the primary a significant question in a presidential campaign is as close to despicable as anything I can imagine."

Gingrich angrily rebuffs questions about ex-wife

Gingrich disputed the allegations as "false," and his three fellow Republicans onstage resisted piling on. ("Let's get on to the real issues," former Massachusetts Gov. Mitt Romney said.)

Recent pollng of the race suggests that Gingrich has been enjoying a late surge in South Carolina, one that could threaten Romney's bid for a win that, his campaign hopes, would all but seal the nomination for the former Massachusetts governor.

An NBC News-Marist poll released Thursday found Romney leading at 34 percent among likely primary voters in the state, followed by Gingrich at 24 percent, Texas Rep. Ron Paul at 16 percent, former Pennsylvania Sen. Rick Santorum at 14 percent, and Texas Gov. Rick Perry at 4 percent. But in the latter half of the two-day poll, following Gingrich's strong performance during a Monday debate, Romney's lead winnowed to five points.

NBC poll: Newt Gingrich gains ground on Mitt Romney in South Carolina
 
South Carolina has correctly predicted the eventual Republican nominee since the inception of its primary in 1980; in each subsequent contest, the winner has gone on to become the GOP standard-bearer.

Romney has sought to project an air of inevitability surrounding his candidacy, but has been dogged by questions about the business practices of Bain Capital, the private equity firm he cofounded, that go to the core of his argument that he is the candidate most experienced to repair the U.S. economy. Romney's work for Bain also made him wealthy, and Romney's GOP rivals have pressed him to release his tax returns.

He dealt with both issues Thursday evening. Romney sought to explain Bain's work in greater detail, highlighting instances in which its work created jobs. He avoided engaging with Republicans, like Gingrich, who have questioned Romney's private sector record.

"I'm someone who believes in free enterprise," he said. "And I'm going to stand and defend capitalism across this country, throughout this campaign. I know we're going to get hit hard from President Obama, but we're going to stuff it down his throat and point out it is capitalism and freedom that makes America strong."

Romney also faced pressure to release his tax returns. He said he would release records -- going back an unspecified number of "multiple" years -- but not until April, by which time the primary may well be settled.

It was Santorum, though, who put the most pointed questions to the two frontrunners. Santorum, who served in Congress while Gingrich was speaker, raised questions about whether Gingrich's conduct as a leader would lead to a "worrisome moment" for the GOP.

"Grandiosity has never been a problem with Newt Gingrich. He handles it very, very well," Santorum said, later adding: "I knew what the problems were going on in the House of Representatives when Newt Gingrich was leading there. It was an idea a minute, no discipline, no ability to be able to pull things together."

That exchange opened up a broader, sharper discussion between the candidates on their backgrounds. Romney characterized Gingrich as a lifelong insider, and again touted his business experience as the best qualification for his candidacy.

"I was in business 25 years. So you're not going to get credit for my 25 years," Romney said. "I don't recall a single day saying, 'Oh, thanks heavens Washington is there for me.'"

But Romney was also put on the spot by Santorum, and later, Gingrich, over his record in Massachusetts. Gingrich accused Romney of continuing to support abortions even after having announced his opposition to abortion rights. And Santorum went on the attack on Massachusetts health care reform.

"It is not a free-market health care system. It is not bottom-up. It is prescriptive and government. It was the basis for Obamacare," Santorum said.

Romney stumbled at moments and offered wonky answers in response to the criticism, repeatedly vowing that, for whatever his past record shows, he would govern in opposition to abortion rights.

"I did my very best to be a pro-life governor. I will be a pro-life president," Romney said. 

Texas Rep. Ron Paul at times fell to the background, having to make quips at moment about not being afforded an opportunity to join the scrum onstage.  At one point, when the moderator was ready to move on after a question on abortion, the crowd complained that Paul hadn't been given an opportunity to answer.

The debate came after one of the most momentus days in the campaign. Perry ended his bid for the nomination and threw his support behind Gingrich, who has shown signs of revival in South Carolina, and who has sought to rally conservatives under the banner of being the best alternative to Romney.

That narrative shaped Thursday night's debate, which saw Gingrich engage in frequent crowd-pleasing answers, dropping references to Ronald Reagan and taking frequent shots at the media.

Whether Romney did much to reverse his slide likely won't be known until Saturday, when South Carolinians head to the polls. Debate settings have been a strength for Gingrich, and he, Paul and Santorum have relished the opportunity to pile on Romney in these settings. (Another debate is scheduled for Monday night in Florida.)

The debate, hosted by CNN and the Southern Republican Leadership Conference, was broadcast at 8 p.m. ET.