DES MOINES, Iowa — Republican Mitt Romney opened a broad and newly abrasive assault on rival Newt Gingrich on Thursday, dispatching surrogates and staff to cast him as unworthy of the GOP nomination and unfit to be president.
Romney is aiming to undermine his rising rival on both personal and professional fronts ahead of the 2012 campaign's opening contest Jan. 3 in Iowa — a reversal by the onetime front-runner who had previously all but ignored his Republican foes.
"He's not a reliable and trusted conservative leader because he's not a reliable or trustworthy leader," former Missouri Sen. Jim Talent, a Romney supporter, said of Gingrich, offering a preview of the attacks Romney's team promised would continue.
Romney allies were giving him a boost, announcing a $3.1 million TV ad campaign in Iowa that is expected to include hard-hitting commercials against Gingrich.
Campaigning in South Carolina, Gingrich brushed off the verbal assault and insisted his campaign would not change its above-the-fray approach regarding fellow GOP contenders.
"We're focused on remaining positive," he said.
Gingrich's reluctance to engage may be out of necessity. He dramatically trails Romney in organizational firepower as he tries to rebuild his campaign after an early summer implosion that left it deep in debt.
The onslaught of criticism from Romney and his allies, after months of focusing solely on President Barack Obama, comes as the race has developed into a two-person contest. Gingrich's quick rise in national and early-state polls threatens Romney's claim as the likeliest Republican to be chosen to challenge Obama next fall.
Romney stayed out of the fray Thursday, raising money in private in Virginia. But he's all but certain to weigh in with a sharp critique of Gingrich when he campaigns today in Iowa.
GOP Candidates debate Saturday: With Newt Gingrich virtually wearing a big target on his back, he and his rivals for the Republican presidential nomination square off Saturday night in the first of two nationally televised debates in Iowa that could prove pivotal to the contest.
Information from McClatchy Newspapers was used in this report.