Hillary Rodham Clinton spent more than $18 million and hired hundreds of employees in the first three months of her presidential campaign, creating a national operation that vastly outpaces her rivals in both parties. 

She has the money for it, having raised more than $46 million for the Democratic primary contest. 

But building a campaign Goliath hasn't come cheap. Clinton spent more than $5.9 million on 343 employees, $700,000 on computers and other equipment, and nearly half a million renting offices, including her 80,000-square-foot Brooklyn headquarters. 

Beyond paying for salaries and space, her campaign purchased lists of voters in four early primary states, paid six figures to a super PAC devoted to defending her record and spent heavily on building a digital team, according to campaign finance documents filed Wednesday with federal regulators. 

It's a strategy aimed at a contest that's nearly a year away. The overwhelming favorite for her party's nomination, Clinton's team has set its sights on building the massive infrastructure they'll need for the general election. 

The outlay is nearly four times what Clinton spent in the first three months of her last presidential campaign, when she faced a far more competitive primary race against then-Sen. Barack Obama. 

During that 2008 campaign, Clinton and her team faced charges from donors that they were wasting money on ineffective strategic choices -- like spending nearly $100,000 for party platters and groceries before the Iowa caucus, a contest she lost. 

This time, her staff has emphasized its "cheapskate" mentality -- particularly to contributors. At her first national finance meeting in May, top donors were instructed to purchase their own lunches and fund their own transportation to various gatherings in Brooklyn. 

Campaign aides like to brag about taking the bus from New York to Washington, rather than the more expensive Acela train. Even so, her campaign spent at least $8,700 on train tickets and just a few hundred dollars on bus fare, the Federal Election Commission report shows. 

All told, Clinton has spent a far greater portion of her early funds during this campaign than she did eight years ago. 

During the first three months of her 2008 bid, Clinton spent 14 percent of the $36 million she raised, according to FEC documents. In the launch of this campaign, she's burned though nearly 40 percent of what she has taken in. 

Her campaign also reported that Clinton received more than 250,000 contributions, with an average donation of $144.89. About 17 percent of her contributions were $200 or less. 

By comparison, Vermont Sen. Bernie Sanders has fueled an insurgent challenge to Clinton with small donations. He pulled in more than $15.2 million through the end of June, and three-quarters of his donations were $200 or less. 

Though they've highlighted their lower-dollar contributions, Clinton's team also released a list of campaign bundlers who each raised more than $100,000 for her primary bid. 

Some of the donors included Clinton's most ardent financial backers, including Hollywood media mogul Haim Saban; Susie Tompkins Buell, a wealthy California investor who was a major donor to the Ready for Hillary super PAC; Las Vegas publisher Brian Greenspun, a longtime friend and college classmate of Bill Clinton; billionaire J.B. Pritzker of Chicago; and Alan Patricof, a New York-based financier who served as Clinton's finance chair when she first ran for Senate in New York. 

Clinton's team also successfully courted some of Obama's biggest backers, including New York financiers Marc Lasry, Charles Myers and Blair Effron. 

Others included former Clinton aides like Minyon Moore, Tom Nides and Lisa Caputo, former Indiana Sen. Evan Bayh, and current members of Congress like Reps. Jim Himes of Connecticut and Grace Meng of New York.