Like the interspecies friendship between the Budweiser puppy and the Budweiser Clydesdale, dramatized in the beer-maker’s super-adorable Super Bowl ad, corporations have mined another kind of awww-inspiring alliance for marketing gold: the big business-small business relationship.

It’s a genre whose hall of fame includes American Express’s “Small Business Saturdays,” and now, too, perhaps Intuit’s “Small Business, Big Game” blitz that gave a little company $4 million worth of Super Bowl advertising.

Ken Yancey, CEO of SCORE, a nonprofit association that provides resources to small businesses, has been noticing this B2B trend for years, going back to the early 2000s. “As the economic importance of small businesses, their buying power, and their impact on communities has become widely known,” he says, “more larger companies have focused on them as a market segment.”

For major corporations, such ads are also a way to reach individual consumers with that crowd-pleasing notion of helping Main Street. It’s like saying, “When you’re working with us, you’re also working with all these small companies,” explains Tim Calkins, a marketing professor at Northwestern’s Kellogg School of Management.

But advertisers have to be careful; it’s hard enough creating a message for one brand, let alone multiple brands in the same ad. “It can quickly turn into a jumble,” warns Calkins. For that reason, the Super Bowl advertising critique session Calkins launched for Northwestern MBAs actually handed Intuit’s small-biz commercial a harsh grade of “D.” “One of the issues with the spot was the branding wasn’t very clear,” he says.

Below, check out how Intuit and others have tried to win big with small.