Story highlights Clinton had $33 million in the bank at the end of September; Sanders, $27.1 million

Sanders has raised $3.2 million since Tuesday night's CNN Facebook presidential debate

Washington (CNN) Bernie Sanders is slowly erasing Hillary Clinton's hard money advantage.

Clinton finished the summer fundraising quarter with $33 million in the bank, according to a new filing with the Federal Election Commission. She raised $28.8 million in that July-through-September period for the Democratic primary and spent $25.8 million of it.

But while Clinton has more than any other candidate, Sanders is catching up. He ended the quarter with $27.1 million cash on hand. He raised $26.2 million and spent $11.3 million.

The Democratic presidential rivals are running much different campaigns -- with Clinton's staffing levels and early television advertising buys in Iowa and New Hampshire built around a $100 million fundraising goal for 2015 that she expects to meet, and Sanders still ramping up his organizing efforts.

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