Mitt Romney has dramatically accelerated spending on his campaign for the Republican presidential nomination, burning through nearly as much money as he raised in the third quarter to cover hefty fundraising, travel and consulting expenses.

The former Massachusetts governor brought in $14.2 million in contributions from July to September while spending more than $12 million, according to a report filed with the Federal Election Commission on Friday.

The costs include nearly $3 million for direct-mail services, $3 million for various consultants and $1.2 million for salaries topping out at $160,000 for senior aides, records show. Rent and utilities on his Boston headquarters added up to more than $80,000 a month.

The spending figures were high despite a lack of expensive television ads and stand in contrast to some of his more thrifty competitors. Texas Gov. Rick Perry, for example, spent about $2 million of the $17 million raised from August to September, according to his campaign.

Romney aides said the surge is aimed at building a national organization, and they noted that the candidate stockpiled cash during the early months of his campaign. Romney has spent about 55 percent of the $32 million he reported collecting this year, a rate comparable to that of Barack Obama’s campaign in 2007, aides said.

“This quarter, we invested in the states to build the infrastructure for our grass-roots operations, including additional staff in early primary states, ballot access and voter ID,” said Andrea Saul, a Romney spokeswoman. “We are well prepared to run a 50-state campaign.”

As of two weeks ago, when the reporting period ended, Romney had about as much money on tap as Perry, who is the only other Republican competitor to approach his fundraising ability. Perry’s campaign has faltered badly in recent weeks, however, amid concerns about his debate performances and other issues.

President Obama had four times as much cash on hand at the end of September as did Romney or Perry, and he has spent about 25 percent of the $90 million he has brought in, records show. Obama has raised an additional $65 million for the Democratic National Committee.

The rest of the Republican field lags far behind, and the latest reports raise questions about whether at least one candidate — former Utah governor Jon Huntsman Jr. — can afford to continue. He had $327,000 in the bank and nearly $900,000 in outside debts at the end of the quarter, according to his FEC report.

The Huntsman campaign said last summer that the candidate had raised about $2 million by the end of June. But the records show that it took until the end of September for him to raise $2.26 million; he also lent his campaign $2.25 million.

“Fundraising dried up and the actual results did not match the pledges our campaign had received, so we fell below our anticipated fundraising total in June,” said Tim Miller, a Huntsman spokesman.

The records show Romney continues to rely heavily on the Wall Street and banking sector for financial support, led by U.S. employees of firms such as Barclays Capital, Goldman Sachs, Deutsche Bank and Morgan Stanley. Donors who gave less than $200, by contrast, accounted for only about 14 percent of his total.

Obama is pursuing both the high and low ends of the fundraising spectrum. Nearly half of the $42 million he raised for his campaign in the third quarter came from donors who gave $200 or less.

The campaign also released a list of 351 major fundraisers, called “bundlers,” who have brought in $50,000 or more.

Staff writer Aaron Blake contributed to this report.