(CNN) -- Sen. Barack Obama has asked top contributors to help former rival Sen. Hillary Clinton retire the debt from her failed presidential campaign, an Obama campaign source said.

Obama and Clinton ran a protracted race for the Democratic presidential nomination that left Clinton with a campaign debt of more than $22 million when she bowed out this month.

About $12 million of that amount is money the senator from New York loaned to the campaign herself.

Obama asked members of his National Finance Committee to contribute to Clinton's campaign if they were so inclined, but he did not direct them to do so, the Obama campaign source said Tuesday. Watch how Obama is helping Clinton »

Individual donors can contribute $2,300 to individual candidates. It would take 4,500 contributors donating the maximum $2,300 to pay off Clinton's $10.3 million in debt owed to vendors.

Some of Clinton's biggest debts include $4.6 million-plus she owes to consulting firm Penn, Schoen & Berland Associates, $921,408 to MSHC Partners for printing and mail, and about $500,000 to Electrum Productions for equipment costs.

Speaking about the Clintons, Obama said Tuesday night that "I am going to need them."

Also Tuesday, former President Clinton's office issued a statement saying he is "committed to doing whatever he can" for Obama.

Obama said he and the Clintons will be "working closely together over the next couple of weeks to put together a plan."

"They're going to want to campaign actively on behalf of the Democratic ticket," Obama said.

"Bill Clinton is one of the most intelligent, charismatic political leaders that we have seen in a generation, and he has got a lot of wisdom to impart."

The former president was sharply critical of Obama on the campaign trail earlier this year, and he has yet to endorse the senator from Illinois publicly, even though his wife threw her support to him when she suspended her campaign on June 7.

"[Sen. Clinton's] going to be a force to be reckoned with, not only in the Senate, but hopefully if I'm successful in the White House, she's going to be one of my key partners in making sure that we're moving forward on issues like health care that she cares so deeply about," Obama said.

Obama spoke with his former rival Tuesday and said he looked forward to speaking with her husband soon.

Obama is teaming up with the former first lady for a campaign appearance Friday in Unity, New Hampshire, where they both got 107 votes in the January primary.

CNN's Alexander Marquardt, Chris Welch and Robert Yoon contributed to this report.

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