Chief Financial Officer Jeff Atwater has been working the phones in recent days, telling Republicans activists and donors that he intends to run for the Republican U.S. Senate nomination and wants their support. With incubent Sen. Marco Rubio expected to announce his candidacy for president April 13, Atwater is gearing up for what could be a tough primary for a rare open senate seat. Other Republican prospects include Lt. Gov. Carlos Lopez-Cantera and U.S. Reps. Ron DeSantis,R- Ponte Vedra Beach. Democratic U.S. Rep. Patrick Murphy of Jupiter has already announced his candidacy.