Gingrich can't beat Obama. Hell, as of yet he can't even beat Romney in a Republican primary...that is very worrisome.
Obviously Gingrich isn't trying to beat Obama at the moment. If he gets the nomination his strategy will change, and so too will the polls. But even then the polls won't matter much until sometime around September. So to me all the Obama vs whoever match-ups are nothing but red herrings. They mean no more than polls early on showing that Hillary and Giuliani would end up being the nominees for 2008.
As for Romney, it isn't just Romney that Gingrich is going up against but Romney + virtually the entire Republican establishment. If not for all his money and the establishment backing him, i don't think Romney would even be a factor at this point. With all that, he becomes a formidable candidate, just like Obama by himself would be nothing but Obama with a billion dollar campaign chest + the media backing is going to be tough for anyone to beat. Besides, who else is doing better than Gingrich? Santorum is losing steam and has never particularly stood out in any of the debates. So i don't see how he is going to get his momentum back. Basically he benefited from and continues to benefit from Romney training all his attacks at Newt, leaving Santorum pretty much unscathed so that he can continue to split the conservative vote.
We give too much power to pollsters. Especially with polls projecting something 11 months away in an age where you can see wide changes of opinion in just a week's time.