Evan McMorris-Santoro January 20, 2012, 1:51 PM

This article was updated at 2:09 Eastern to reflect comment from the Romney campaign.

CHARLESTON, SC — Dogged by questions about the tax records he still won’t release, Mitt Romney and his allies are making a last-ditch effort to make the last hours of the South Carolina primary fight about Newt Gingrich’s paper trail.

There’s just one problem: the hidden documents Romney is trying to embarrass Gingrich with are already public record.

At an appearance Friday, Romney told reporters that Gingrich should release the report from the 1990s Congressional ethics investigation that eventually led to a $300,000 fine for the then-House Speaker.

“[House Minority Leader Nancy] Pelosi has a full record of that ethics investigation,” Romney said, according to the Boston Globe’s Matt Viser. “It’s going to get out.”

Romney’s comments pivot off a similar attack on Gingrich from one of his main surrogates, the former New Hampshire governor John Sununu. On a conference call Thursday, Sununu warned of an “October Surprise” caused by Democrats exposing what’s inside the ethics report. Sununu seemed to insinuate that this report was confidential, but that its contents were known by Pelosi because of her time on the House ethics committee. “Whatever Pelosi knows, Obama knows,” he warned reporters, saying that Democrats must be “laughing with glee behind closed doors.”

Both Romney and Sununu appear to be referring to comments made by House Democratic Leader Nancy Pelosi to TPM last month. She said Democrats were ready for Gingrich to become the nominee, and pointed to the “thousand pages of his stuff” she reviewed while on an ethics panel investigating him.

Gingrich seized on the comments at the time, accusing Pelosi of violating ethics committee confidentiality rules. But her office struck back quickly, saying the documents Pelosi was referring to are already public. Pelosi’s staff responded to an inquiry from TPM today by referring back to her statement from December in which she stressed she was talking about documents already in the public realm. Indeed, you can read the enormous report for yourself here. Of course it’s possible that Pelosi was having her cake and eating it too, and was coyly hinting at secret files in order to stir the waters; however, since then her office has studiously maintained that her words refer to public documents.

The Romney campaign responded to an inquiry from TPM, saying that they were referring to material that went into the writing of the report which was not made public. Friday afternoon, Romney spokesperson Gail Gitcho sent out this statement to reporters:

“Given Speaker Gingrich’s newfound interest in disclosure and transparency, and his concern about an ‘October surprise,’ he should authorize the release of the complete record of the ethics proceedings against him. We know from Newt’s own statements that he turned over a million pages of documents. Nancy Pelosi, who sat on the ethics committee, said that this information contains damaging information. Nancy Pelosi is gleeful over the information she has on Speaker Gingrich, and Speaker Gingrich is concerned enough to threaten her with a rules violation. If Nancy Pelosi has this information, Barack Obama has this information.”

The campaign gave this citation:

Gingrich: “We Turned Over 1 Million Pages Of Material” To Ethics Investigators. “In response, Gingrich said at a Dec. 5 news conference that the House should retaliate if [Pelosi] violates confidentiality rules, something Pelosi’s staff said she won’t do. ‘We turned over 1 million pages of material,’ Gingrich said. ‘We had a huge report.’” (Bloomberg, 12/8/11)

However, as stated above, Pelosi has already said she was referring to the final (public) report, and not the documents which went into the researching of it. As with any publicly released report, the conclusions of the final document synthesize the materials that went into it, meaning the Democrats insist the “surprise” is already out there. So Romney’s attempt to deflect talk of his own still-hidden tax records may just have backfired badly. Instead of showing what Gingrich has hidden, he’s very neatly pointed out that much of Gingrich’s past is essentially an open book.

2012, 2012 Presidential Primaries, John Sununu, Mitt Romney, Nancy Pelosi, Newt Gingrich