Newt Gingrich has reverted to rogue, and his anger may cost the Republicans the White House. As he did years ago when denied a good seat on Air Force One, Newt had decided to get mad and even, but this time the slight came in the form of Mitt Romney’s attack ads, and the retribution is not a government shut-down, but the attempted shut-down of Romney’s candidacy. If the collateral damage is once again to Republicans generally, as it was when Newt threw his 1995 hissy fit, then so be it. Newt has vengeance in his eyes.

Consider what his super PAC “Winning our Future” is doing in South Carolina. Bolstered by a $5 million contribution from a casino owner, it is saturating the airwaves with an ad attacking Romney’s record as head of a private equity firm. As many have noted, the notion that a Republican is attacking a fellow Republican for being an aggressive and successful capitalist is strange enough. But what is even more remarkable is that Gingrich is directly parroting one of Obama’s central general election arguments against Romney.

Will the ad work? My guess is that it will hurt Romney among Republicans where it runs. There is a strain of economic populism in Republicans; it shows up in the Tea Party’s antipathy to Wall Street bailouts and large corporate salaries. The ad paints Romney as a kind of modern-day carpetbagger or mill owner, who exploits workers for his personal gain. The consequence of this negative portrayal could be a prolonged nomination fight and a weakened Romney. But that would be satisfactory for Newt. For him, that is what passes for victory these days.