Florida Rep. Connie Mack IV (R) today got the endorsement of presumptive GOP White House nominee Mitt Romney, boosting his effort to win the GOP nomination to take on two-term Sen. Bill Nelson (D).

“Connie Mack is a friend, a strong conservative and the type of principled leader we need in Washington to restore fiscal responsibility,” the former Massachusetts governor said in a statement. “By electing Connie Mack, the people of Florida will be sending a clear message to Senator Nelson and President Obama that their failed policies have not worked to change the borrow and spend ways of Washington.”

Mack, who strongly supported Romney in the Florida GOP presidential primary, faces former Sen. George LeMieux in the Sunshine State GOP Senate primary, which will take place Aug. 14.

Even in a presidential tossup state such as Florida, Nelson has an edge in the race, as he is widely expected to outperform President Barack Obama in November. Roll Call rates the Florida Senate race as Leans Democratic.