With scant evidence, a new commercial by Republican Linda McMahon asserts that Democrat Richard Blumenthal profited from a settlement he and other attorneys general made two years ago with the mortgage giant, Countrywide Financial.

McMahon’s Senate campaign takes the premise of a recent magazine article–that the settlement turned out to be a good deal for Countrywide’s parent, Bank of America–and introduces a startling new suggestion that Blumenthal was corrupt, because his family now owns the bank’s stock.

“Her $50-million attack machine has shifted into desperate,” Blumenthal said Wednesday night.

Not only did Blumenthal dispute the suggestion that the settlement benefited Bank of America, he said that his family owned none of the bank’s stock when he joined 10 other attorneys general in suing and settling over predatory lending practices.

“We reached the settlement in 2008. The stock was bought in 2009. The facts just absolutely belie and decimate that statement in the ad,” Blumenthal said. “This ad is just outrageously false.”

A financial disclosure form required of Senate candidates says that Blumenthal’s wife, Cynthia, has invested up to $1.25 million in D.C. Capital Partners, which has holdings in 19 companies, including Bank of America. It does not state when the investments were made.

One of two 60-second commercials McMahon began airing Wednesday, the ad links Blumenthal to Sen. Christopher J. Dodd and an issue that helped drive Dodd from the race: his ties to Countrywide Financial.

The ad goes on the air as McMahon, the former chief executive of World Wrestling Entertainment, also is showing voters a softer side in the final two weeks of a campaign that Blumenthal still leads in all polls.

In a new mailing, McMahon seems intent on lowering the temperature of the heated race, saying in a letter, “Dick Blumenthal is not a bad man. He wants to help our state, too.” And in her second new TV commercial, an emotional McMahon talks about a campaign encounter with a single mother.

But the Countrywide ad, the second the campaign has aired on the subject in a week, lands like a punch.

“We know about Chris Dodd and his sweetheart deals with Countrywide, but did you know about Dick Blumenthal?” a narrator asks. “Blumenthal cut a deal with Countrywide that let the mortgage giant off the hook for billions, a deal that raided the retirement funds of teachers, firemen, policemen and state employees.”

Then the ad supplies a motive: “Even worse, turns out Blumenthal is an investor in the mortgage giant.” It’s conclusion: “Dick Blumenthal, he took care of Countrywide and took care of himself, just like Chris Dodd.”

McMahon has previously attacked Blumenthal’s truthfulness, primarily over his false references to service in Vietnam, and his 20-year-record as the state’s longest-serving attorney general.

But this is the first time that McMahon, who has poured a record $41.5 million of her own money into her first run for public office, has asserted that Blumenthal compromised his office.

“To make the contention is absolutely unconscionable,” Blumenthal said.

Ed Patru, the communication director of McMahon, stood by the ad.

“I’m saying that every part of this advertisement is factually accurate,” Patru said.

Patru said Blumenthal failed to take additional action against Bank of America in 2009 after purchasing the stock. It is unclear what action Patru thinks Blumenthal could have taken, given that the suit was settled in 2008.

“I think people understand what it means when a politician invests in a bank and then refuses to take action against that bank,” Patru said.

Blumenthal said he recently took adverse action against the banking industry by seeking a moratorium on foreclosures, a response to allegations that banks falsified records to pursue foreclosures.

Countrywide emerged as a potential issue last week when The Nation published an article contending that Bank of America eventually avoided much of the liability for a settlement requiring the bank to write off principal and interest owed on troubled loans.

The article said that a bailout program enacted by the Obama administration in 2009 ultimately saved Bank of America as much as $4.5 billion of the $8.6 billion settlement. It also said that investors who bought securitized mortgages from Countrywide, including public pension funds, bore the brunt of the write-down.

Blumenthal said he still believes the settlement was a good deal for mortgage holders, a contention disputed by The Nation.

“This deal accomplished its goals at the time. It kept thousands of people in their homes in Connecticut and it held Countrywide accountable,” Blumenthal said. “Months later, the administration restructured the bailout program, which I opposed. That fact was unforeseeable at the time.”

In an interview Wednesday before the ad was released, McMahon made no claim that Blumenthal personally profited from the settlement with Bank of America, a company in which she and her husband own stock worth up to $65,000.

“It absolutely just came to our attention, and it is complex,” McMahon said of The Nation article. “But the bottom line, as it seems to me, is Countrywide was not held accountable for those mortgage-backed securities that it sold.”

Dodd’s troubles with Countrywide involved market-rate mortgages he obtained on homes in Connecticut and Washington. As part of a “friends” program, the company allowed him to take advantage of falling interest rates after he locked in his mortgage. The Senate’s Ethics Committee found no wrongdoing.

In the McMahon ad, Blumenthal is pictured with Dodd next to a headline about the friends program, which did not involve Blumenthal.