Presidential candidate and former Massachusetts Gov. Mitt Romney's position as the default front-runner in the race for the 2012 Republican nomination may finally be catching up to him, according to recent polling numbers. 

Presidential Candidate Newt Gingrich (Gage Skidmore, via Creative Commons)

While other candidates' popularity -- from Michele Bachmann to Rick Perry to Herman Cain -- has tanked as fast as it rose, Romney's has stayed relatively stable. That is looking to change as polling ahead of the Iowa caucuses, which take place in early January, shows former House Speaker Newt Gingrich ahead of Romney by a significant margin in that state.

The developments have been a surprise to many observers who long considered Gingrich a lower-tier candidate.

The latest NBC News/Marist Poll shows Gingrich with an eight-point lead over Romney in Iowa and a 21-point lead among Tea-Party supporters, a surprising turn given Gingrich's long history as a Washington insider. The latest ABC News/Washington Post poll also gives Gingrich the lead.

Interestingly, Romney's support is also comparatively low among people who get most of their news from Fox News, according to a New York Times poll. The polling indicates a "less-than-perfect relationship between Mr. Romney and the network that many conservatives view as their primary source for political information," according to the New York Times.

A recent interview of Romney by Fox News host Bret Baier got awkward when the interviewer pushed Romney to explain alleged changes in his positions over the years, particularly on health-care. 

Romney's front-runner status has attracted attacks from not only his fellow Republican candidates but from Democrats who have also been viewing him as the inevitable candidate against President Barack Obama. 

The Democratic National Committee has release videos attacking Romney, including one that latched on to his claim that the government should stop trying to stop the foreclosure crisis and let the housing market "hit the bottom" and rebound on its own.

Romney has also taken heat for his tepid position on the extension of payroll tax cuts, which Obama has proposed. He recently came out in support of the extensions. 

Some analysts have been positing what a Gingrich candidacy would mean for the Tea-Party, which was credited with the surge of Republicans elected to Congress in 2010. 

The Tea Party can't elect Gingrich without betraying its "core principles," writes Conor Friedersdorf at the Atlantic, noting that the Tea-Party movement was, in part, a reaction to the "big-government" policies of the Bush administration:

He favored No Child Left Behind, an unprecedented federal intervention in education. He supported Medicare Part D, a brand new, budget-busting drug entitlement. He supported "comprehensive immigration reform," perhaps the most divisive-among-conservatives policy initiative of the aughts. He urged the passage of TARP. And he even spoke favorably about the infamous Harriet Miers nomination, a George W. Bush misstep that caused many of his most loyal supporters to rebel. 

Tea Partiers pledged that if they had their way the GOP would never again have as its champion a federal government enlarging, entitlement expanding, amnesty urging, Bush-style Republican.

To do so just four years on would be a significant failure.

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