Old and busted: Mitt Romney doesn’t need Iowa to win the nomination.  New hotness: Romney needs to show some strength to slow down the runaway momentum of Newt Gingrich.  The super-PAC backing Romney, Restore Our Future, has secured a massive ad buy of $3.1 million in Iowa to convince caucus-goers to line up on Romney’s side in four weeks:

Mitt Romney’s SuperPAC is going up on TV for the first time, launching a massive $3.1 million TV and radio ad buy in Iowa aimed to shore up Romney’s flagging poll numbers there.

The ad itself is pretty good, and focuses solely on Barack Obama and not any of Romney’s Republican competitors. Clearly, though, the super-PAC wants to contrast Romney’s experience as an executive in the public and private sectors with more than just the current Chief Executive:

Politico wonders whether this will raise expectations for Romney’s performance in Iowa, and whether he can meet those raised expectations:

The aggressive investment could bolster Romney’s standing in Iowa, where he’s slipped to a tie for second place with Ron Paul in most polls. It’s also sure to up expectations there for Romney, who has taken a cautious approach for much of the year toward the caucuses.

To give a sense of perspective on this ad buy, it’s almost three times what Rick Perry’s campaign spent on its own “saturation”-level purchase this week.  It’s almost the amount of money that Gingrich’s campaign announced that they had raised in the first half of the quarter.  A three-million buy in Iowa means this ad and others to follow will be running almost constantly between now and the caucuses on January 3rd.

The issue won’t be whether Romney can win Iowa, although a win here could have a game-over effect for Gingrich and the rest of the field.  Romney needs to erode Gingrich’s momentum so that Romney can compete in states like Florida, where a new Survey USA poll puts Gingrich up 22 points over Romney.  At 45/23, the primary in that state has come down to a two-candidate race, as no one else is polling above 6%.  The same kind of result — although less stark — is seen in the latest Quinnipiac poll of Florida, where Gingrich leads 35/22 and no other candidate gets above 8%.  Quinnipiac also polled other swing states, and as National Journal notes, Gingrich is gaining momentum as a serious candidate in the general election as well as the primaries:

President Obama is underwater in key swing states, and faces electoral peril in November from both Mitt Romney and Newt Gingrich, according to new polls released early Thursday by Quinnipiac University, which show Gingrich surging among Republicans in three important battlegrounds,

Gingrich, the former speaker of the House, leads the GOP field in each of the states — Florida, Ohio and Pennsylvania — by double-digit margins. But perhaps more importantly, his ascent has not been confined to the Republican primary: Gingrich now runs only slightly worse against Obama than Romney, the former Massachusetts governor. …

[B]oth Gingrich and Romney pose significant threats to Obama in the race for Ohio’s 18 electoral votes. Gingrich and Romney both run neck-and-neck with Obama, leading him by identical, hair’s-breadth margins, 43 percent to 42 percent. …

Obama runs slightly stronger in Pennsylvania than in the other two swing states. He leads Romney, 46 percent to 43 percent, up from a one-point edge last month.

Against Gingrich, Obama leads by a wider margin, 48 percent to 40 percent. Last month, Gingrich trailed Obama by 10 points.

Romney has had an advantage on general-election electability, until now.  He needs to slow Gingrich’s rise and start generating some of his own momentum if he wants to keep from getting swamped out of the primaries first.  Expect to see more Romney efforts in Iowa in the next couple of weeks.  He has a big financial advantage over Gingrich, and it’s now time to apply it.