Old campaign debts and a tax lien may be the first bumps in the campaign trail for Alan Keyes, the Maryland conservative expected to accept the Illinois GOP nomination for U.S. Senate on Sunday.

Keyes, who ran for president in 1996 and 2002, owes $524,000 for his failed presidential bids, according to Federal Election Commission documents. Debts for 1988 and 1992 U.S. Senate races in Maryland have been settled.

And tax records indicate the State of Maryland in 2001 filed a tax lien on the home owned by Keyes, 54, and his wife, Jocelyn, because of $7,481 in unpaid state income taxes and penalties.

On Friday, Keyes was able to pay off the tax debt with a certified check for a little more than $152, said William Pascoe, a longtime friend of Keyes' who is volunteering as his spokesman.

A spokesperson for the Maryland state comptroller's office said, however, that the debt "hasn't been satisfied," and was unable to confirm whether Keyes had made arrangements to pay the tax debt.

The lien resulted from what Pascoe called "an erroneous tax accounting" involving payments for speeches by Keyes to a personal corporation he formed to handle money he makes as a public speaker, Pascoe said.

Former Illinois Atty. Gen. Ty Fahner, who screened potential GOP Senate candidates, said they all were asked whether they had failed to file any state or federal income taxes. And they were asked if they had any outstanding issues with the Federal Election Commission, which regulates campaign spending in federal campaigns.

Though some Republican sources said they believed Keyes had not fully disclosed all his campaign debts, two state central committeemen said he told the committee, which nominated him Wednesday, that the debts were being taken care of.

"The majority of the outstanding debt is money that is due and payable to longtime Keyes staff and operatives," said Pascoe. "They fully expect to settle the campaign's debts within short order of coming to final agreement with the FEC."

At the committee meeting, when asked about his outstanding campaign debts, Keyes "said everything is being finalized and worked out," said state Sen. Dave Syverson (R-Rockford).

Douglas Webber of the Center for Responsive Politics in Washington, D.C., said it is not unusual for candidates to allow debt to accrue for years in losing campaigns.