The former Massachusetts governor and former head of Utah's 2002 Winter Games made the pronouncement amid a five-day California swing that includes 11 fundraisers, and just before a lobbying group's fundraiser for him in Washington. Romney also said he would likely contribute more to his campaign before the fundraising quarter ends Monday, although he declined to say how much.
To date, the venture capitalist has contributed $9 million to his campaign, nearly a quarter of his overall contributions.
"I don't like the fact that money has such an impact on politics, but this to me is a reason I'm investing at least as much as everybody else - probably a little more," Romney told about 200 people in an airport hangar.
"I'm not beholden to any particular group for getting me into this race or for getting me elected. My family, that's the only one I'm really beholden to, they're the ones who let their inheritance slip away, dollar by dollar."
In noting that he had "contributed significantly to the campaign," Romney added: "I presume I will again."
Despite separating himself from special interest groups, Romney will be the beneficiary Thursday of a fundraiser held by the Dutko Group, a Washington-based lobbying firm. Among its members is Ron Kaufman, a former political adviser by President George H.W. Bush and one of Romney's top strategists.
An invitation to the event, posted online by Politico.com, read: "Thank you for joining me in supporting Governor Mitt Romney and committing to raise $1,000, individually or as part of a team, at Washington, D.C.'s, upcoming rally."
Asked about the invitation, Romney spokesman Eric Fehrnstrom told The Associated Press: "Mitt Romney is an outsider who is not beholden to the special interests. By far, he is the single biggest contributor to his campaign."
Romney began his fundraising in January with an eye-popping $6.5 million haul at his first event, but at the time he told reporters that contributing to his campaign "would be akin to a nightmare." While saying he reserved the right to do so, and in fact having already done so by the time he made the comment, he explained he wanted to build a broad apparatus of donors.
Meanwhile, a new CNN/WMUR-TV poll in the early voting state of New Hampshire showed that former New York Mayor Rudy Giuliani has pulled into a statistical dead heat with Romney, with Romney garnering 23 percent of the vote and Giuliani 22 percent. In July, Romney had a clear lead, 33 percent to Giuliani's 18 percent.
Romney dismissed the findings, telling reporters "the polls bounce up and down," but adding: "I'm pleased with the fact that a guy that was in the single digits is in the double digits and up there in the leading group, and I hope I can continue that throughout the process."
He also expressed optimism for the GOP as well as himself, telling the crowd, "The Democrats are looking strong right now but they're overplaying their hand. We're going to knock them out; don't worry. We're going to keep the White House."
The town-hall meeting was a noisy affair, as airplanes and helicopters took off from adjacent runways. Just across Long Beach Airport was the factory for the C-17, the Air Force cargo plane that has become a workhorse in the Iraq war.
One questioner asked Romney what he thought about his father, former Michigan Gov. George Romney, saying in 1968 that he had dropped his support for the Vietnam War despite being subjected to "a brainwashing" by U.S. generals during a tour of Southeast Asia. The elder Romney suffered amid misguided questions about his mental health.
Mitt Romney said: "He didn't mean, literally, 'brainwashed.' It was a metaphor, an expression, to suggest we weren't told the truth. ...He said to me, 'In politics, being right too early is always a mistake.' But he didn't care. He was right too early."
