CEDAR RAPIDS, Iowa (AP) — Republican presidential candidate Mitt Romney dived into his campaign’s full-scale critique of rival Newt Gingrich on Friday, standing by top supporters who described the former House speaker as self-serving and mocking some of his ideas about science and technology.

In return, top Gingrich backers described Romney’s criticism as a sign of panic less than four weeks until the Iowa caucuses begin the 2012 nominating contest. Gingrich has risen to the top of Iowa polls in the past two weeks and is leading in some other states, too.

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While Gingrich kept to his pledge not to criticize his GOP rivals, he reignited criticism for being a loose cannon by referring to the Palestinian people as being an “invented” people.

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Romney said in Des Moines that he stood by former New Hampshire Gov. John Sununu, who described Gingrich on Thursday as “self-serving” and “anti-conservative” for criticizing a Medicare provision in House Budget Chairman Paul Ryan’s budget.

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Romney also hinted at their larger career differences, a theme that could come up during Saturday’s nationally televised debate in Des Moines and in television ads before the Jan. 3 caucuses.
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