Mitt Romney is a Swiss-bank-account-owning liar. So says Newt Gingrich.

Newt Gingrich officially drops out of the presidential race Wednesday, and the Obama campaign is celebrating with a video that trashes Mitt Romney – in the words of Mr. Gingrich.

Talk about low-hanging fruit. All the Obama camp needed to do was collect the most pungent of Gingrich’s attacks on Mr. Romney during primary debates and interviews, add a heavy dose of sarcasm, and stir.

Gingrich is throwing his support behind Romney?, the video asks.

“As a man who wants to run for president of the United States who can’t be honest with the American people, why should we expect him to level about anything if he’s president?” the former House speaker asks matter-of-factly in one clip.  

Next question: Is it Romney’s business record that Newt supports?

“You’d certainly have to say that Bain at times engaged in behavior where they looted a company leaving behind 1,700 unemployed people,” Gingrich says, referring to the private-equity firm that Romney formerly headed.

Then: “There was a pattern, in some companies, a handful of them, of leaving them with enormous debt, and then within a year or two or three, having them go broke. I think that is something he ought to answer.”

Follow that with slams on Romney’s Swiss bank account, a “Romney machine” that’s “not capable of inspiring positive turnout,” positions that are “anti-immigrant,” and another attack on Romney’s honesty, and you’ve got a tidy message against the presumptive GOP presidential nominee.

Romney finished the competitive part of the primary season with the lowest likability of any major-party nominee in modern history – thanks in part to attacks from Gingrich and the other GOP candidates. Now Gingrich is reportedly set to endorse Romney in the next couple of weeks. The Obama campaign is making sure we don’t forget what Gingrich thought just a few months ago.