DES MOINES - Mitt Romney's SuperPAC, Restore our Future, this evening released an ad accusing Newt Gingrich of "flip flopping" on issues while having "tons of baggage," though the ad quickly disappeared from You Tube where it had been posted.

The ad, titled "Smiling," opens with an image of President Obama, and asks the question, "Why is this man smiling?"

"Because his plan is working," says the voiceover. "Brutally attack Mitt Romney and hope Newt Gingrich is his opponent."

"Why? Newt has a ton of baggage like the fact that Gingrich was fined $350,000 for ethics violations, or that he took at least $1.6 million from Freddie Mac just before it helped cause the economic meltdown."

"Then there's the $37 million Gingrich took from health care and industry groups," the ad continues. "And on the issues? Newt's been on all sides. He supports amnesty for millions of illegal immigrants."

"And Newt was a longtime supporter of a national health care insurance mandate, the centerpiece of Obamacare. Maybe that's why George Will called Gingrich the least conservative candidate."

"The Gingrich record: 30 years in Washington, flip-flopping on issues," the ad concludes, directing viewers to "check the facts at Newtfacts.com."

A spokeswoman for Restore our Future had no comment on the ad, but sources said it was "unfinished" and not meant to be published.

Asked about the ad, Gingrich responded, "This is only the very beginning of what will be an onslaught of attacks and distortions coming from both sides of the political spectrum. The trick is voters aren't interested in it and they don't believe it.

"They're looking for someone who can bring the country forward," Gingrich added. "We're confident in giving the people the truth and the facts will outweigh what the critics are doing."

The Romney campaign also did not return a request for a comment.

The 60-second ad, at one point posted on You Tube, has now been removed from the website.

Earlier today, Restore our Future announced a $3.1 million ad buy in Iowa for a 30-second ad. Watch that ad HERE.

While the SuperPAC is not affiliated with the Romney campaign, an analysis by ABC News in August found that it is funded by many of the same people who have contributed to Romney. It is also staffed by several of Romney's former staffers.

About half the money given in the first fundraising quarter to Restore our Future came from donors who also gave the federal maximum of $2,500 to Romney's campaign. And of the $12.2 million raised by the PAC, more than $6 million was given by Romney campaign donors.

Another way to look at it is that of the 90 donations to the PAC, approximately 57 came from Romney donors, although in some cases it was difficult to ascertain from a Federal Election Commission report if identical names represented the same person. For instance: Paul Edgerly, who works at Romney's former company, Bain Capital, donated the maximum $2,500 to the actual Romney campaign. However, he gave $500,000 to the SuperPAC. What's more, his wife Sandra did exactly the same thing. Marriott hotel heirs JW Marriott Jr. and Richard Marriott, each gave $500,000 to the PAC, on top of their donations to the campaign. (FYI, Willard Mitt Romney is named after the "W" in the original J.W. Marriott.)

James Davis, CEO of New Balance Sneakers, also gave $500,000 to the SuperPAC and the co-CEOs of Sun Capital each threw in an additional $125,000."