UPDATE: Microsoft on Sunday released the final minute-long spot.

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Microsoft's first national ad in the Super Bowl is a tear-jerker starring former NFL player Steve Gleason, now battling Lou Gehrig's disease.

Mr. Gleason played for the New Orleans Saints and became locally famous (there's a statue of him outside the Superdome) for blocking a punt in the Saints first home game after Hurricane Katrina. He now uses a Surface Pro tablet with eye-tracking technology to speak.

Microsoft is big ad spender -- $1.23 billion in the U.S. in 2012, according to Ad Age Datacenter -- but the company has never bought a national ad during the big game.

The ad will feature a number of inspiring stories including Mr. Gleason's and direct viewers to a website that has more. Microsoft hasn't released the ad, which will run at 60 seconds during the fourth quarter, but it did release three vignettes that are part of the campaign. Microsoft declined to say who made the ad.

Why now? Spokesman Lou Gellos said Microsoft's Xbox and Surface are NFL sponsors and Bing is partner with the Seattle Seahawks. "It seemed like the logical next step," he said. "It didn't hurt that our local team is in the game."