For the big soda companies, it's become necessary to latch on to -- and aggressively market -- any bright spots. So when PepsiCo noticed Wild Cherry Pepsi outpacing the category, it set about creating a robust marketing plan to support the cola, even though it controls just shy of 1% of the soft-drink category.

"Flavored colas are having a good time. When you think about, look at the future of the cola category, they may be a more important part of the portfolio," said Simon Lowden, Pepsi Beverages North America chief marketing officer.

According to Beverage Digest, Wild Cherry Pepsi grew 2.9% last year, compared to a 3% decline for the entire carbonated soft drink category.

"When you see that kind of sunshine, you have to step on the gas," said Lou Arbetter, senior director-marketing at Pepsi, adding the brand is popular with millennials and multicultural consumers. "It was an opportunity to coordinate a full media-to-shelf marketing plan."

This spring, PepsiCo has invested in TV, digital, mobile, out of home, radio and sampling, in addition to food service integrations with brands like Little Caesars for Wild Cherry Pepsi. The company created special displays for retailers, in an effort to gain visibility and incremental shelf space. And at a local level, there are integrations with the National Cherry Festival in Traverse City, Mich., and text-to-win programs.

Mr. Arbetter declined to say what PepsiCo is spending on the campaign. The brand worked with Los Angeles-based Pitch, Barbarian Group and Tracey Locke.

It's been years since Wild Cherry Pepsi saw any sort of significant marketing support. Launched in 1988, the extension, which also has a diet version, spent just $83,000 on measured media in the last five years, according to Kantar Media. There was some TV support for the brand in the early 2000s, tied to the NFL Playoffs. But PepsiCo execs and industry insiders alike were hard pressed to recall any sort of major media support for the brand in recent history.

"Certainly, in recent years, it's unusual to see dedicated support behind an older brand of this scale," said John Sicher, editor and publisher of Beverage Digest. "Though most of [Coca-Cola and PepsiCo's] bigger brands are not growing, some of the smaller brands are, and they need to find a way to cost effectively support these smaller brands with marketing. ... Coke and Pepsi need to be able to do more than just market their big mega brands, in order to be as competitive as they can be."

Pepsi has been focused on a trademark, or masterbrand, approach this year, preferring to put its marketing muscle behind ads that feature multiple brands -- Pepsi, Diet Pepsi and Pepsi Max, in the case of an ad airing during the Academy Awards. The dedicated push for Wild Cherry is counter to that. Mr. Lowden said the brand is committed to a trademark approach for big events, like the Super Bowl and Academy Awards, but there will be times it makes sense to have "spikes" in communication around individual brands or packages.