With the first Republican nominating contest a little over two weeks away in Iowa, Romney made his first appearance on a Sunday television talkshow since March 2010 to try to recapture the lead in the race to run against Democratic President Barack Obama in November.
"If we go on for months and months, we will have the resources to carry a campaign to each of the states that will decide who gets delegates and who becomes the nominee," the former Massachusetts governor told "Fox News Sunday," saying he was "prepared" for a protracted primary battle.
Preparing the ground in Iowa, his campaign unfurled endorsements this week from former Republican leader Bob Dole, Iowa's influential Des Moines Register newspaper and South Carolina Governor Nikki Haley.
But despite vast resources and a well-oiled campaign organization that put him in the lead for months, Romney has struggled to take command of the race that has seen one candidate after another surge in the polls, only to fall back.
Gingrich, whose campaign nearly imploded early on, has managed a stunning comeback from the political dead, soaring in the polls over Romney on the strength of canny campaign performances and tepid conservative support for the former governor.
His rise also has brought sharp warnings from former House colleagues of his personal and political failings as a leader.
Romney attacked him for opposing Republican orthodoxy on key issues, like reform of the Medicare health insurance for the elderly, and his penchant for futuristic ideas.
"He has been unreliable in those settings and zany," Romney said. "I wouldn't think you'd call mirrors in space to light highways at night particularly practical or a lunar colony a practical idea. Not at a stage like this."
True to form, Gingrich refused to take on Romney directly, saying only that he was "delighted" his rival had won the endorsement of the "liberal" Des Moines Register.
Instead, the former House speaker devoted much of an interview on CBS television's "Face the Nation" to defending his controversial view that presidents should simply ignore Supreme Court rulings at times.
But the two White House contenders agreed on one thing -- that Obama was wrong in his "precipitous" withdrawal of US troops from Iraq, warning of greater Iranian clout and violence in the strife-torn country.
"People do not understand how much the Iranians have penetrated Iraq, and that the vacuum we've created will lead to, I think, a very, very unstable and very unpleasant environment in Iraq," Gingrich said.
And a "very concerned" Romney pointed to Obama's failure to secure an agreement with Iraq over stationing US troops there, saying "we should have left 10-, 20-, 30-thousand personnel there to help transition to the Iraqi's own military capabilities."
There are some indications that Gingrich, like others before him, has slipped with the increased scrutiny.
A Rasmussen Report poll on Thursday found that he had sunk in Iowa 12 points from a month earlier to 20 percent, and Romney was once again in the lead in the all-crucial state at 23 percent.
Longshot candidate Ron Paul garnered 18 percent, while conservative darlings Rick Perry and Michele Bachmann held 10 percent and nine percent respectively.
Seeking to regain momentum, Romney has turned to others to try to overcome what has proved to be a stubborn reluctance on the part of conservatives to support his candidacy.
In an advertisement in the Des Moines Register, Dole, a former presidential candidate and senator from Kansas, praised Romney's "strong work ethic, rock-solid conservative values and a deep sense of service to others."
Haley insisted that Romney's focus on "jobs, jobs, jobs" made him the right choice for the times.
Iowa barely figures in the general election, but its January 3 caucus is the first Republican contest and so has become key to narrowing the field in the presidential nominating contests.
