The last ad the Karl Rove–backed Crossroads GPS ran against Elizabeth Warren, which sought to tie her to violence at Occupy Wall Street, was one of the most disingenuous and inaccurate ads of the 2012 cycle. Their new ad against Warren is even worse—ludicrously suggesting that Warren supported the Wall Street bailout and has done the bidding of the biggest banks.

First Crossroads claimed that Warren was the intellectual godmother of Occupy Wall Street. Now they’re claiming she’s Wall Street’s best friend. So much for consistency!

Simon Johnson does the fact-checking that Crossroads GPS obviously didn’t bother to do. He notes at least five major inaccuracies in the new ad:

1. TARP was a Republican program—proposed and implemented by President George W. Bush. At the time, Ms. Warren was busy championing people whose rights had been trampled by the financial sector through various kinds of abuses.

2. Ms. Warren became chair of the Congressional Oversight Panel (COP) for TARP, precisely because people in Congress—on both sides of the aisle—trusted her to provide an honest and professional check on the support provided to financial firms. She did her highest profile work during the Obama administration, bringing relentless pressure on the Treasury and other agencies who just wanted to prop up big firms without any conditions.

3. Ms. Warren has also been a strong supporter of all efforts to rein in Too Big To Fail banks, including by breaking them up. She has consistently been one of the strongest advocates for curtailing the abusive power of megabanks (and others who have behaved badly).

4. At the same time, Ms. Warren has not demonized the financial sector. On the contrary, when charged with setting up the new Consumer Financial Protection Bureau, she went out of her way to work closely with those in the financial sector who provide sensible products with reasonable conditions. Her emphasis throughout has been on transparency, fairness, and full disclosure in this sector. You are not allowed to sell dangerous toasters in the United States; her point is that you should not be allowed to sell financial products that have been proven dangerous.

5. The idea that Elizabeth Warren would ever side with “big banks” against the middle class is preposterous. Time and again, she has stuck up for the middle class (and anyone who uses financial services) – even when it was deeply unfashionable to do so. The big banks have opposed her relentlessly and on-the-record, both directly and through various surrogates

In a way, the Crossroads ad, despite its blatant falsehoods, is an admission that Warren’s brand of progressive populism is deeply resonant with voters. Her message of accountability for Wall Street and advocacy on behalf of consumers scares the bejesus out of Republicans. Indeed, in a new Boston Herald poll, where Warren leads Scott Brown by seven points, voters say they trust Warren more than Brown to fight for middle-class families and effectively regulate Wall Street.

In other words, Republicans are conceding that they can only defeat Warren by lying about her record and making it appear that she coddled Wall Street, when in fact her entire career has been about doing precisely the opposite. My guess is that this ad, like the last Crossroads ad, will backfire stupendously.

PS: Today Republicans also voted to filibuster the nomination of Richard Cordray to head the Consumer Financial Protection Bureau that Warren founded.