Hillary Clinton has raised questions about Democratic rival Barack Obama's use of a political action committee to funnel money to Democratic candidates in New Hampshire and other key early voting states.

Through the fund - commonly referred to as a leadership PAC - Obama has given $73,000 to New Hampshire candidates and Democratic committees from July through November, according to a report filed with the Federal Election Commission. Several of those candidates have endorsed Obama, some after receiving a donation.

At issue is how candidates use their leadership PACs, which are designed to distribute money to other candidates and political committees. Candidates are forbidden from using leadership PACs to directly advance their campaigns, campaign finance experts said. After the Washington Post reported the donations earlier this week, the Clinton campaign released a statement implying that Obama was flouting campaign laws.

"It is our understanding that a candidate's campaign is barred from using the candidate's leadership PAC to benefit his or her campaign which is why we shut down Hill PAC when Senator Clinton announced her run for the White House," the statement said. "On the campaign trail, Senator Obama is outspoken about his desire to reform the campaign finance system, so it was surprising to learn that he has been using his PAC in a manner that appears to be inconsistent with the prevailing election laws."

Obama's campaign responded by denouncing the statement and upping the conflict, attempting to demonstrate larger differences between the candidates on financial disclosure.

"Whatever happened to the confident frontrunner who said she wouldn't attack other Democrats just two weeks ago?" Obama spokesman Bill Burton said in a statement. "The latest personal attack from Hillary Clinton is a completely false attempt to misrepresent Barack Obama's full disclosure of his campaign finances.

"Senator Obama's commitment to disclosure is one that Hillary Clinton does not share, and until Senator Clinton is willing to make this commitment by disclosing her White House records, the list of donors to her husband's presidential library, how much her bundlers raise, and releasing her personal tax returns to the public - she's not really in a position to point fingers at others," Burton said.

The Obama campaign response prompted more reaction from the Clinton camp. "Instead of launching irrelevant attacks, Sen. Obama should answer a simple question: Did Obama campaign officials direct the (PAC) to make contributions to officials and entities in states holding nominating contests?" Clinton spokeswoman Kathleen Strand said. "If the answer is no, they should just be direct and say so."

The Obama campaign's attorney, Bob Bauer, maintained that the PAC's activities were entirely within bounds. "It's really a political attack because it has no merit at all as a legal attack," he said.

Leadership PACs

Critics of leadership PACs argue that they allow candidates to sidestep some fundraising regulations, since donors can contribute more to a leadership PAC than a campaign: A leadership PAC donor can give $5,000 a year, while donors can give only $2,300 to a political campaign for each election, said Paul Ryan, an attorney at the nonprofit Campaign Legal Center.

"Leadership PACs have become a wide-open slush fund," Ryan said.

In theory, he said, candidates aren't allowed to use leadership PACs to advance their own presidential campaigns. Most politicians considering a presidential run will create leadership PACs, which allow them to lay the groundwork for a campaign before they officially announce their candidacies.

Candidates "use them to pay for repeated trips to New Hampshire, Iowa and South Carolina two or three years before an election to talk about issues," Ryan said.

And as long as the candidates don't mention that they're running for office, they can use leadership PAC money, he added. If a candidate visits an early voting state "just to talk about the war in Iraq or minimum wage or right to life, and you're carefully coached by your attorney to stay away from talking about your candidacy, you pay for it" with the leadership PAC.

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