Published: May 16, 2012 8:14 PM EDT

TALLAHASSEE, Fla. (AP) - Republican presidential contender Mitt Romney says Connie Mack IV is his choice in Florida's GOP primary race for the U.S. Senate.
    
Romney announced Wednesday his endorsement of Mack, a congressman from Fort Myers, over former Sen. George LeMieux.
    
It's rare for presidential candidates to thrust themselves into primary races for other offices, but Romney said Mack is a friend. In a statement, the former Massachusetts governor also said Mack is a strong conservative who would oppose the "borrow and spend ways of Washington."
    
The Republican nominee will face incumbent Democratic Sen. Bill Nelson in November. A spokeswoman for LeMieux declined comment.
    
Mack said in a statement that he was humbled by Romney's endorsement and they would work together to unseat Nelson and President Barack Obama.

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