Florida Republican Senate candidate Marco Rubio says he has nothing to hide about his use of a credit card issued through the state GOP.
Gov. Charlie Crist, his rival in the GOP nomination for the U.S. Senate, had asked federal prosecutors to investigate credit cards used by more than two dozen party and elected officials.
The scrutiny comes at a crucial time in this year's race for the U.S. Senate, with polls showing Rubio with a substantial lead in the primary against Crist.
The Miami Herald/St. Petersburg Times, citing unnamed sources, reported that investigators are looking into credit card use for a number of GOP leaders in Florida to determine if they were used for personal expenses.
Rubio said he has not been contacted by any investigators.