WASHINGTON – As Election Day approaches, President Obama is burning through campaign money faster than he can collect it — exceeding his spending pace at this stage of the 2008 contest as he expands his field operation and trades combative ads on the airwaves with Republican rival Mitt Romney.

Last month alone, Obama spent nearly $59 million through his main campaign account — $10 million more than he raised, financial reports filed late Monday afternoon show. The cost of his campaign so far: more than $325 million, not counting spending by the the Democratic Party committees aiding his re-election.

By contrast, President Bush had spent $205.4 million to retain the White House at this point in the 2004 election.

The Democratic National Committee also stepped up its spending on the president's behalf last month, burning through $32 million — more than double what the national party spent a month earlier, as it undertook fresh rounds of polling and advertising to help Obama.

The president's new investments included additional staffers. He employed 853 people in July, up from 779 a month earlier, a USA TODAY analysis shows. Romney had 326 staffers on his payroll last month, up from 272 in June.

Obama pumped more than $48 million into advertising last month, more than twice what Romney spent.

The Romney campaign has been on a winning streak when it comes to fundraising, besting Obama and Democrats for three straight months. Romney and his fundraising operation reported collecting $101 million in July, outgunning Obama and his allies by $25 million.

Since then, the Romney camp said it has raised $10.2 million online in the week after Romney's Aug. 11 announcement of Wisconsin Rep. Paul Ryan as his running mate.

Overall, Romney has spent $165.3 million through his main campaign account since the beginning of last year, but he must wait until after he is formally nominated at next week's Republican National Convention in Tampa to draw on his substantial general-election funds. In the interim, he has been helped by super PACs and other Republican-aligned independent groups, which can raise and spend unlimited amounts, but are barred from coordinating their activities with candidates.

The candidates and super PACs aiding them were required to report details of their July fundraising before midnight Monday.

Obama's spending has put increased pressure on his campaign to raise money quickly. In an e-mail to supporters last week, he implored them to give as little as $3 each, saying he was being outspent by Republicans on the airwaves by a 2-to-1 ratio in Iowa. Next week, the hunt for cash heads to Europe where actor George Clooney is scheduled to headline an Obama fundraiser in Geneva.

Other reports filed late Monday highlight the role that a handful of wealthy donors, corporations and unions play in bankrolling super PACs:

•A pro-Romney super PAC, Restore Our Future, reported raising almost $7.5 million in July. The largest donor was Texas homebuilder Bob Perry, who donated $2 million and has given $7 million total. Another $1 million came from the Renco Group, which includes AM General, maker of the military's Humvee vehicle.

Four members of the Lindner family of Cincinnati donated a combined $500,000, while three companies affiliated with the owners of The Villages retirement community in Florida donated a total of $200,000.

•American Crossroads, a Republican-aligned super PAC, raised $7.1 million in July. Texan Robert Rowling was the biggest donor, giving $2 million personally and through his company, TRT Holdings, which owns Gold's Gym International and the Omni Hotel chain.

•Priorities USA Action, a super PAC aiding Obama, lagged behind Republican groups. It raised $4.8 million in July. Donors included Philadelphia real-estate developer Mel Heifetz, who gave $1 million, and New York-based architect Jon Stryker, who contributed $750,000.

•PayPal co-founder Peter Thiel, who spent heavily to advance Texas GOP Ron Paul's president campaign, donated $1 million in July to Club for Growth Action, which has backed upstart, anti-tax candidates in GOP primaries for Congress.

•Two labor unions donated heavily last month to a super PAC working to help Democrats gain seats in the U.S. House. The House Majority PAC took in more than $760,000 in July. The International Brotherhood of Electrical Workers was the largest donor, emerged as the biggest donor to the group, giving $350,000. The International Association of Firefighters gave $250,000.

•Ending Spending Action Fund, a super PAC created by T.D. Ameritrade founder J. Joe Ricketts reported collecting nearly $400,000 last month, most of which came from Ricketts. Ricketts, a billionaire whose family owns the Chicago Cubs baseball team, was at the center of controversy earlier this year when news broke that his political operation was weighing anti-Obama ads that linked the president to the incendiary remarks of his former pastor, Jeremiah Wright. Ricketts said he rejected the proposal.