DALLAS -- Mitt Romney's presidential campaign borrowed $20 million in the month of August to pay for its expenses before he could begin tapping general election dollars and is now $11 million in debt, a senior campaign official confirmed late Tuesday.

Romney's campaign finance filings, due to be released on Wednesday, will show the campaign with $15 million in debt, the official said, although the debt currently stands at $11 million.

The National Review Online first reported news of the campaign's debt Tuesday night.

Although Romney has raised hundreds of millions of dollars in general election funds, his campaign could not legally tap those funds until after he officially was nominated at the Republican National Convention. Through the summer, he could only spend primary dollars, and once that money dried up the campaign was forced to borrow money to pay its bills.

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