For Summit Brewing Co. and Minneapolis ad agency Gabriel deGrood Bendt, less is more.

Although it seems counter­intuitive, the pioneer craft brewer and its marketing partner have made an empty beer glass the center of a five-year advertising campaign.

“We did focus groups and found that an empty beer glass did the best job of making people thirsty for a Summit,” said Doug deGrood, GdB’s creative director. “We had no idea it was going to work that way but it did.”

And the results are in the barrel, so to speak.

In the five years that Summit and GdB have been together, Summit production has increased nearly 37 percent from 82,371 barrels in 2008 to 112,451 barrels last year.

“We’ve had steady growth of 8 to 10 percent a year,” said Carey Matthews, Summit’s marketing coordinator. “It’s been consistent.”

The GdB-engineered campaign uses the catch phrase “Get to the bottom of it” and shows a glass draped with foam residue on the inside with one last sip at the bottom. And, to add humor to the ad, a rhetorical question that doubles as a bar conversation topic is pasted next to the near empty glass.

“We have a state flower, why no state beer?” read one online banner ad in 2010.

“If Facebook tells me I have 500 friends, where were they all on moving day?” said an online post in 2011.

“How did the pilgrims survive Thanksgiving without football?” was another tongue-in-cheek question asked last year.

In an increasingly competitive world of craft beer, distinguishing oneself from others is critical to survival, especially in a market such as the Upper Midwest where craft beer sales increased by 16 percent in 2011, according to Advertising Age.

“If there were 10 choices of craft beer when we first started working with Summit in the early 1990s there are 20 more choices today,” said Stephanie Shimp, executive vice president of the Blue Plate Restaurant Co., which owns seven Twin Cities spots including Groveland Tap and the Edina Grill.

“The consumer is so much more savvy now and is educated and eager to try new products,” Shimp said. “But Summit is the leader and has laid the [craft beer] foundation for the Twin Cities.”

Summit, which brewed its first batch of beer in 1986, is a relative senior statesman in the Minnesota craft beer sector.

“To the younger craft beer drinker, Summit is perceived as a mature brand,” deGrood said in an interview. “We’re striving to re-energize it and make it relevant to its core customer as well as the new, younger customer.”

As a result, deGrood said, the Summit advertising campaign has “a very democratic mix” of traditional media and new media from billboard and radio spots to Facebook and online displays.

Jennifer Johnson, a brand strategy instructor at the University of Minnesota School of Journalism and Mass Communications, said the GdB-Summit campaign is perfect for the craft beer aficionado.

“The bottom line is that this is a craft beer that appeals to people who are more interested in having a conversation than having a buzz,” Johnson said. “Enjoying a craft beer is about sitting down with the beer and enjoying the people your with.”

GdB was honored in 2011 for its Summit campaign by the Outdoor Advertising Association of America, which presented the agency with a gold OBIE award, its top honor. GdB was recently named a finalist for a 2012 OBIE.

Summit said it chose GdB to market its product because the agency was local and not too big.

“We needed a full-service agency but we didn’t want one so big that we’d get lost [among other clients],” Matthews said.

GdB, a 16-year-old agency, has a staff of a little more than 30 with offices in downtown Minneapolis. Its client list ranges from food manufacturer Crystal Farms to Anytime Fitness.

The Summit campaign also lets individuals enter a contest with their own question where the monthly winner gets a $50 Summit gift card for use in the brewer’s gift shop.

The entry of a “Hillary H.” from St. Paul was featured on one Summit bar coaster where she asked, “Which is a better social medium — beer or Twitter?”

“Dan O.” from Ely won for this question: “Why can’t we invent a grass that only grows 2 inches tall?”

“We didn’t know until we ran the billboards that this campaign was ripe for consumer engagement,” deGrood said. “The consumer smells a forced sell a mile away and tends to be less receptive. You need to grow organically. The perfect environment to engage people is in the bar.”

The crown jewel of the Summit campaign is an 8-foot-tall, 4-foot-wide digital billboard on Block E in the Warehouse District of Minneapolis where it’s virtually impossible for fans leaving Target Center and Target Field to miss.

The billboard, which is visible in the spring and summer, shows a tall glass of Summit ale evolve into an empty glass with always-present questions such as “What is the ideal beer-to-brat ratio?” and “Why is it called ice fishing if you’re not fishing for ice?”

“It’s fun and humor. We like that,” said Matthews.