“This is permitted by Federal Election Commission rules,” the aide explains. “In the past, the FEC has specifically contemplated candidates putting up their public financing payments as collateral.” Since Romney is not taking public funds, his finance team found another option.

In order to compete with President Obama, the senior aide continues, Romney’s advisers could not sit on their hands until they were able to use general-election funds.

So far, $9 million has been paid back. Five million was paid back before the end of August and an additional $4 million has been paid back in September.