Barack Obama's bracket from 2009.
Barack Obama's bracket from 2009. whitehouse.gov

Filling out a bracket and joining a pool has become a March tradition for Americans.

People who don't pay attention the entire basketball season pick winners in the NCAA Tournament, hoping to win some cash.

There are ways for you to win more than a few bucks by filling out a bracket.

Multiple online sports websites give you a chance to win some serious cash.

ESPN's Tournament Challenge gives you a shot to win a $10,000 Best Buy gift card. Contestants who finish in the top one percent will be entered into a random drawing for the prize.

CBS's Bracket Challenge allows someone who finishes in the top 10 percent win the grand prize--a trip to the 2013 Final Four.

Yahoo Sports will pay $10,000 to a contestant with the best bracket. The site will also give $5 million to anyone who has a perfect bracket.

In order to be perfect, someone would have to predict all 63 games in the Tournament.

Don't expect that to happen. The odds of picking a perfect bracket are 9,223,372,036,854,775,808-to-1.

Fox Sports has also pledged to give $1 million to anyone who chooses every game correctly.

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