Tim Tebow, Tom Brady take on tough endorsement challenges

— -- Tom Brady and Tim Tebow are plenty marketable. But the two quarterbacks have two prominent deals that aren't exactly in slam-dunk endorsement categories: men's shoes and underwear.

But it's not clear how much that has to do with sales of men's shoes. There are plenty of mixed messages.

Investors were bullish Wednesday and the stock spiked higher. But Deckers insiders might not feel the same way. Its chief marketing officer Angel Martinez, a long time marketer for Reebok who recruited Brady, cashed in $736,000 worth of stock on Tuesday. As of Friday, the stock has lost much of its Wednesday pop.

Tebow, meanwhile, is the new face of Jockey. The private company signed him last year, but has gotten more aggressive in the past couple weeks, offering $1 million in free products if the Broncos win the Super Bowl and splashing him on the front page of their website.

But the underwear category is a sensitive one. Does showing Tebow shirtless, dressed only in his underwear, appeal to men? That's going to be the job of Dustin Cohn, Jockey's chief marketing officer, who once worked at Element 79, which was Gatorade's chief ad shop.

It's a tough challenge for both Martinez and Cohn to take two on categories that traditionally aren't associated with men.

In an unscientific CNBC Twitter poll, (256 of my followers voted), 80% said an endorsement by neither Tebow nor Brady would get them to buy underwear or boots, while 11.7% would buy what Tebow is selling and 8.3% said they'd go with what Brady was pitching.

But the relatively unchartered waters in this space (yes, Michael Jordan has pitched basic briefs and T's for Hanes for years) could make it more satisfying.

If anyone can break down barriers, it might be these two.

An ESPN Sports poll this week reflected that, for the first time, Tebow was the most popular athlete in the country. And Brady's not too shabby. He came in No. 5 in NFL jersey sales this year to Tebow's No. 2, even though you'd figure everyone who wanted a Brady jersey would have one by now.

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