The RNC disclosure came in an unannounced RNC filing Friday with the Federal Election Commission, Politico reported.
The filing showed the RNC raised slightly more than $5.5 million in July, less than half what the Democratic National Committee brought in, and spent $11 million.
The RNC, led by Chairman Michael Steele, had more than $2 million in debt.
Other GOP committees are doing better raising money, Politico said.
The National Republican Congressional Committee, for example, outraised the Democratic Congressional Campaign Committee, $8.5 million to $6.2 million, in July.