On Tuesday night, Mitt Romney went off.

At a campaign event in Ohio, Romney said that "this is what an angry and desperate presidency looks like," adding: "[Obama's] campaign strategy is to smash America apart and then try to cobble together 51 percent of the pieces. If an American president wins that way, we all lose.”

The reaction by Romney was all the more notable because he is almost always in total control on the campaign trail -- projecting a sunny demeanor amid the hurly-burly of the race.

Romney aides insisted in the wake of his blow-up that it had not been pre-planned or strategized about in any way. It was, they argued, Romney unplugged.

On one level, that explanation makes sense. Remember that Romney is the ultimate rule-follower, someone whose entire life has been defined by his ability to rapidly learn the rules that govern any situation, internalize them and then succeed within them. (It's why Romney was good in business and successful in debates — both bound by lots and lots of rules of the road — and far less good on the stump, a more free-form sort of exercise.)

When Romney feels like the rules have been broken, he reacts emotionally — or as emotionally as he ever gets. Remember Romney's testy exchange with a questioner in an August 2011 town hall? Or his appeals to CNN's Anderson Cooper during a back and forth with Texas Gov. Rick Perry in a GOP presidential debate?

It's clear from his response on Tuesday night that Romney feels as though the rules of engagement have been repeatedly broken by Obama — from the president refusing to condemn a Democratic super PAC ad that tries to link Romney to the death of a woman to Vice President Joe Biden's assertion earlier in the day that a Romney presidency would "put ya'll back in chains".

Regardless of whether or not Romney's flash of anger was purposeful — our guess is it wasn't -- it does land in the middle of a presidential campaign and, therefore, is likely to have some effect on the race.

President Obama's campaign is working hard to cast it as evidence of a personality flaw in the Republican nominee; an Obama spokesman used the word "unhinged" to describe Romney's reaction — a decidedly purposeful choice of words.

What Republicans have to hope is that Romney's newfound aggression — his detractors would call it anger — on the campaign trail can a) convince people that he is not simply a political robot carrying out the mission as best he understands it and b) chip away at President Obama's massive likability gap.

As we have written before, people  — even many who dislike his policies — like President Obama.  On virtually every character trait, Obama has a wide lead over Romney. And, while the Romney team has long dismissed the gap as less important than the fact that a majority of Americans disapprove of President Obama's handling of the economy, they also know that presidential elections are not won or lost on issues alone.

Personality matters. The presidential vote is as much about the person voters feel most comfortable with as it is about the person who lines up with them on every single issue. That goes double for independent and unaffiliated voters.

By going at Obama's approach to politics, Romney is — whether intentionally or not — seeking to undermine the "hope and change" messaging on which the President's likability edge is built.  It's unlikely that Romney can ever make himself more likable than Obama but if he can erode some of the good will directed at Obama the person, he may be able to narrow the gap.

Using anger/aggression in politics is a dangerous game. Too much of either can be a major turnoff for voters who tend to like measured equanimity in their pols. But, for Romney, who has labored under the caricature of an emotionless automaton for seemingly forever, showing some emotion may wind up being a good thing.

The question going forward is whether Tuesday night represents a turning point in how Romney presents himself to voters or simply a blip on the radar, quickly forgotten.

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