It's not often that a 125-year-old brand can reinvigorate itself without a complete reinvention. But that's what Narragansett Brewing Company has been able to do. With a shoestring media budget of just $100,000 and guerilla-style word-of-mouth marketing, the brand has been revived, even moving past its New England roots and expanding to markets in the southern United States and on the West Coast.

Once a New England staple—Narragansett was the Boston Red Sox's official sponsor from 1946 to 1975, and it was the beer can famously crushed in Jaws—the brand began to flounder after Midwest beer company Falstaff Brewing Corp. purchased it in 1965. The beer eventually lost favor and was struggling when native Rhode Islander Mark Hellendrung acquired it a decade ago.

Now president and CEO, Hellendrung says he "took a look at what makes [the Narragansett] brand click" and found that "a lot of it is just the history of it, the localness of it and our deep ties to New England." Since changing hands, Hellendrung said, the brand has seen double-digit revenue growth each year, up to $12 million in 2014 from just $100,000 in 2005.

Now a staple in cities like New York; Washington, D.C.; Philadelphia; and Portland, Ore., Narragansett is growing its market share and ranking, now No. 37 on the Brewer Association's Top 50 U.S. Craft Brewing companies. According to Hellendrung the brand has in the last six months worked its way into new markets in Maryland, Delaware, Pennsylvania and North Carolina.

As part of its guerilla marketing strategy, the brand creates a calendar featuring local women, deemed "Gansett Girls." Using pin-up fashion and poses, the brand features a local woman as "girl of the week" on its site. The women then compete for online votes to be in the annual calendar.

Narragansett employs Philadelphia-based creative shop Quaker City Mercantile to design its packaging and shape the voice of the brand. The brand uses a slogan on its 16-ounce cans that dates to the early 1900s: "Made on Honor, Sold on Merit." Hellendrung said the slogan "embodies the brand."

According to consultants, it makes sense that Narragansett Brewing Company has been able to grow with little advertising.

"Beer is as trendy as fashion among young adults—and equally prone to fickle tastes and the 15-minutes-of-fame syndrome," said Roy DeYoung, senior vp of creative strategy for marketing shop PM Digital. "When a historic, regional brand seeks new markets, many of them have huge success in the first wave of cult-like appeal. The story, the mystery and, in the case of Narragansett, the traditional America … and nostalgia we all long for makes it a favorite—at a great price point."

Michelle Snodgrass, director of strategy and communications planning at Vizeum, agreed. "It makes a lot of sense that Narragansett found a place within the U.S. beer market," said Snodgrass. "The craft beer category has been booming in the U.S."

A change in the definition of craft beer is helping that boom along, she added. Last year the Brewer's Association lifted a requirement of using barley malt, which allowed mainstream brewers like Yuengling and Schell's as well as Narragansett to enter the market.

"To many consumers, even before the Brewers Association rule change, Narragansett was perceived as a craft beer, making it a good entry-to-craft alternative for consumers with a lower price point," said Snodgrass.

Hellendrung credits Narragansett's "mash-up" flavors with some of its recent success. Narragansett partnered with Rhode Island lemonade brand Del's to create the citrus-flavored beer known as the Del's Shandy.

It also partnered with Autocrat Coffee Milk for its Coffee Milk Stout. And drawing on its Rhode Island roots again, it created a series honoring Providence author H.P. Lovecraft, whose horror stories have gathered a cult following since his death.

On social media, Narragansett has been able to grow a decent following with over 11,000 followers on Instagram, over 20,000 followers on Twitter and more than 48,000 likes on Facebook.

"Regarding the marketing of beer, there are really three factors that make craft beer successful: Influencers, customer relationships and presence," said Snodgrass. "All three of those factors need to be working in harmony to see real success. Influencers need to be talking favorably about your brand, you need to be using media in a way that builds true relationships with your consumers, and you need to be readily available for purchase on and off premise.

"It's apparent, looking at what Narragansett has done, that they have been using social media, branded content and events and distribution to keep these factors balanced," said Snodgrass.