Charleston, South Carolina (CNN) - Florida Senate candidate Marco Rubio defended himself Monday after a news report revealed that two political committees he started while serving in the Florida House spent heavily on operating costs and payments to relatives, but did little to help other Republicans seeking office.

"The whole story is based on false premises," Rubio told CNN Monday during a fundraising swing through South Carolina with one of his top political patrons, GOP Sen. Jim DeMint. "It costs money to be in politics and that's what the committees were for."

The story, published Saturday in the St. Petersburg Times and Miami Herald, said Rubio started one political committee, Floridians for Conservative Leadership, in 2003. The committee only doled out $4,000 to GOP candidates, but spent nearly $90,000 on political consultants, $14,000 in reimbursements to Rubio and over $50,000 in credit card expenses, according to the report.

A second committee, Floridians for Conservative Leadership in Government, paid thousands of dollars to "couriers" - several of whom were Rubio's relatives. A top supporter of Rubio's opponent in the Florida Senate primary, Gov. Charlie Crist, accused Rubio and his family of "living off" the committees – a charge the Rubio campaign vehemently denied in the story.

Rubio said it's not uncommon for members of his political operation to be family members. He said the relatives were "staffers that worked on our campaign."

Rubio's campaign has acknowledged that the relatives should have been listed by bookkeepers as campaign aides, but said the candidate did nothing wrong.

Those family members, Rubio told CNN, were paid "for work delivered."