Microsoft will unveil a new tagline for its search engine, "Bing is for Doing," with a big-budget spot during the NFC championship game this Sunday.

The campaign, from Publicis Groupe 's Razorfish, will feature winter-sports athletes. The first spot uses Bing searches to tell the story of American snowboarder Kevin Pearce, whose tragic accident quashed his Olympic hopes.

The new campaign plays on the "ing" in Bing as the gerund form of verbs: doing, living, healing, etc.

Ad Age reported in September that Bing was ready to kill the "Decision Engine" tagline created by former agency JWT and used since the relaunch of Microsoft search in 2009.

The shift comes as Microsoft makes modest gains in its share of the U.S. search market. Google leads, with a 65.9% share in December, according to ComScore. Microsoft holds 15.1% vs. Yahoo's 14.5%.

Microsoft's online ad revenue was up 13% in the most recent quarter, primarily because of search, the company reported yesterday.

Razorfish has been handling TV work for the brand, Bing General Manager Danielle Tiedt told Ad Age in recent weeks.