Newt Gingrich will return this weekend to the same presidential circuit that denied him the nod, boosting instead the candidacy of one-time rival Republican Mitt Romney at a GOP confab in Columbus.

“We have an absolute obligation to defeat Obama,” Gingrich will tell party honchos and and activists huddled for the Georgia Republican Party convention.

That sentiment, to be pressed at Friday night fundraiser and separate speech Saturday to the full gathering, marks only the launch of the former House Speaker’s Romney cheerleading:

Gingrich said there are plans for the two of them to appear together in Las Vegas at the end of the month. In June Gingrich said he will be raising money in Atlanta for Romney and U.S. House Speaker John Boehner, with a Gingrich-Romney tandem appearance set for June 11.

And as the Obama reelect sharpens its knives to carve up Romney’s venture capital work at Bain, Gingrich offered some unsolicited advice to the president: been there, done that, didn’t work.

This week the Obama campaign released an ad along those same lines. Gingrich said his experience should be a lesson to Obama: “that dog won’t hunt.”

Gingrich said the attack will not resonate in voters’ minds as they think: “You want me to be mad because in one company somewhere Romney may have in fact been involved in someone losing their job while you as president have been involved in millions of people losing their jobs?”

– James Richardson