Hedge fund manager Ken Griffin backing Marco Rubio for president

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Citadel's Griffin backs Rubio for President

Ken Griffin, the billionaire hedge-fund manager who has become a major Republican Party donor in recent years, is throwing his support behind Florida Sen. Marco Rubio for president.

"I'm really excited to be supporting Marco Rubio," Griffin, who is the founder and chief executive of the Chicago firm Citadel, said in an exclusive interview with CNBC. "He will be the next president of the United States."

Griffin deliberated for months over whom to support, giving $100,000 apiece to political action committees supporting the Florida U.S. senator as well as Republican rivals Jeb Bush and Wisconsin Gov. Scott Walker. Griffin has spoken admiringly of Walker's stern stance toward labor unions and smaller government. After Walker dropped out of the race in September, Griffin spent weeks mulling whether to support Bush or Rubio.

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