March Madness is here, and the biggest stars in sports, entertainment and politics are getting in on the fun.

From President Barack Obama to country superstar Tim McGraw, it seems everyone filled out a bracket for the Big Dance.

Here's a look at some of them:

President Obama

Biggest first-round upset: (13) Hawaii over (4) Cal

Final Four: Kansas, Texas A&M, UNC, Michigan State

Champion: Kansas

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Minnesota Timberwolves PG Ricky Rubio

Biggest first-round upset: (14) Green Bary over (3) Texas A&M

Final Four: Miami, Oklahoma, UNC, Michigan State

Champion: UNC

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CNN's Wolf Blitzer

Biggest first-round upset: (14) Buffalo over (3) Miami

Final Four: Kansas, Duke, UNC, Virginia

Champion: Virginia

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Kansas City Royals 1B Eric Hosmer

Biggest first-round upset: (14) Fresno State over (3) Utah

Final Four: Kansas, Oklahoma, Michigan State, UNC

Champion: Kansas

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Denver Broncos LB Von Miller

Biggest first-round upset: (13) Iona over (4) Iowa State

Final Four: Kansas, Texas A&M, UNC, Michigan State

Champion: Texas A&M

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PGA golfer Jordan Spieth

Biggest first-round upset: (14) Fresno State over (3) Utah

Final Four: Kansas, St. Joseph's, West Virginia, Michigan State

Champion: Kansas

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Pittsburgh Steelers WR Antonio Brown

Biggest first-round upset: (10) Syracuse over (7) Dayton

Final Four: Kansas, Oklahoma, Indiana, Michigan State

Champion: Oklahoma

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Country singer Tim McGraw

Biggest first-round upset: (11) Michigan over (6) Notre Dame

Final Four: Kansas, Texas, UNC, Virginia

Champion: UNC

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Los Angeles Clippers PG Chris Paul

Biggest first-round upset: (10) Syracuse over (7) Dayton

Final Four: Kansas, Oregon, North Carolina, Virginia

Champion: North Carolina

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Yahoo's Katie Couric

Biggest first-round upset: (15) Weber State over (2) Xavier

Final Four: Kansas, Duke, Kentucky, Virginia

Champion: Virginia

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