Unlike some of his GOP presidential rivals, it wasn't an embarrassing brain freeze, or an ill-conceived bet, that caused Rick Santorum to explode on social media, it was his wardrobe.

The Santorum sweater vest has taken the internet by storm, spawning a Twitter handle (@FearRicksVest) and hashtag (#FearTheVest), a Facebook page and even a YouTube video. The Santorum campaign has even started sporting vests emblazoned with the campaign's logo.

But while the sleeveless sweater is becoming hugely popular on the web, the same is not true in the realm of political fashion , an arena traditionally dominated by suit jackets and ties.

"Sweater vests? No, they are not popular," said men's fashion expert Hendrik Pohl, the CEO of ties-necktie.com. "The sweater vest is more a New England preppy look that I personally wouldn't associate with politics."

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Santorum's sweater vests have made their internet debut at the same time that the former Pennsylvania senator is surging in the Iowa polls.

In Tuesday night's Iowa caucus Santorum made an impressive second-place showing, falling short of beating Mitt Romney by a mere eight votes.

His sudden surge is  drawing ever more media attention and as the scrutiny strengthens, Hendrik said his sleeveless selection may prove to be a smart decision.

"Maybe they are more comfortable for him when he's under fire," he said. "He has his armpits clear and can breathe a little more."

Santorum is not the only candidate opting for comfort over tradition on the campaign trail.

Mitt Romney has ditched the ties and jackets that dominated his 2008 campaign in favor of open collars, rolled-up sleeves and even, as the men's magazine Esquire described them, "a pair of denim that could only be described as Dad Jeans."

Romney's fashion transformation may not be one for the fashion magazines, but it may serve to re-enforce the message he is trying to send to small-town caucus-goers.

"It's pretty obvious to me they want to appear like the guy that you would invite over to Thanksgiving dinner: approachable, down-to-earth, not too rigid," Hendrik said.

The two candidates' more laid-back wardrobe approach seems to have paid off in Iowa where they finished in a virtual tie that was too close to call until the wee hours of Wednesday morning.

Ron Paul, who finished 3,000 votes behind Santorum to take the bronze in Iowa, has not jumped on the casual-wear bandwagon. Paul is most often seen sporting suit jackets and slacks, even throwing on a tie for many of his Iowa campaign events.

Paul's more formal fashion choices are not without their critics.

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The Washington Post's The Fix blog has, without fail, tweeted about Paul's jacket being distractingly too big during every debate. After the Las Vegas debate, for example,  The Fix said that Paul's jacket was "at least two sizes too big" and "made Paul look tiny, never a good image to project when you are running for president."

Paul is both the oldest and smallest male candidate in the race, but his often oversized jacket does little to help him appear larger on TV, Hendrik said.

"You can work with other colors or patterns if you want to look bigger, but wearing clothes that are too big makes you look smaller or that you're dressed in your dad's suit," Hendrik said.

Rick Perry is also a fan of suit jackets while stumping through rural Iowa. He is rarely seen wearing anything less formal, at least from the ankles up. Perry's most notable fashion choice is, without question, his footwear.

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The Texas governor occasionally sports his custom-made, 9/11-inspired, brown ostrich cowboy boots that are emblazoned with American flags and the words "Liberty" and "Freedom."

At a campaign stop in Waverly last week, Perry opted for Justin Roper work boots instead, and Iowans took notice . When one supporter asked where his boots were, Perry said they couldn't stand the test of the Iowa weather.

"You might notice that it's snowing out there too, and I like that extra cushion and insulation underneath the bottom of my feet," Perry said. "Those leather bottom boots, they get a little slick and they get a little cold, so I've learned a few things while in Iowa."

Whether the candidates are donning sweater vests or cowboy boots, Hendrik said their campaign trail style makes a "huge difference" on the impression they make on voters.

"People say first impressions are formed in the first few seconds of meeting someone," he said. "What you wear, what colors you wear, how well you are put together, whether you are shaved or not, all make a huge difference."