Analysis: GOP race has yet to fully test Romney

◼ Mitt Romney’s surprisingly easy rise to the top of Iowa presidential polls, aided by his GOP rivals’ in-fighting, masks vulnerabilities he will have to confront eventually. - Boston.com

Romney has run a smart, nearly mistake-free campaign so far. But his string of luck and efficiency might have a dark lining. He hasn’t been forced to hone incisive answers to tough questions certain to rise in debates if he faces only one or two remaining GOP opponents, or Obama.

Romney appears testy on the rare times when pressed about his policy shifts and his Massachusetts program that required residents to obtain health insurance. Democrats enjoy replaying a Nov. 30 Fox News interview of Romney expressing irritation at such questions.

But Romney has benefitted from a relatively weak field of rivals who, from the start, mostly criticized each other in hopes of becoming the party’s conservative alternative.

◼ York: In GOP ad war, why did Romney get off easy? - Byron York/Washington Examiner

The intensity of the Romney attack, which got an assist from a bitter anti-Gingrich ad aired by Ron Paul, was nearly unprecedented. A new report from the nonpartisan Campaign Media Analysis Group shows that nearly half -- 45 percent -- of all political ads aired here in Iowa have been attacks on Gingrich. There are seven candidates in the race who might air commercials promoting themselves or attacking someone else, and yet nearly half of all ads have been attacks on one candidate.

So here's the question: If negative ads are so effective in bringing down a baggage-laden front-runner, where are the attacks on the current baggage-laden front-runner, Mitt Romney himself?