Republican presidential candidate Newt Gingrich may not appear on the ballot for the June 26 Utah primary, after a $500 check - the required filing fee - bounced, an official said.

State election director Mark Thomas told ABC News that a $500 check given by the Gingrich campaign to secure his place on the Utah ballot bounced on March 27.

"Our office immediately attempted to contact the campaign and the designated agent but no phone calls were returned," Thomas said. "We also asked the state Republican Party to assist us, but they also could not get into communication with them, although I do not know how they attempted to contact them."

One source close to the campaign told ABC News that the Gingrich campaign recently changed finance and accounting staff. The designated agent who filed the paperwork for the campaign was Wallace Woodruff "Woody" Hales, though Hales still works for the Gingrich campaign.

If the fee is not paid by April 20, Gingrich will be disqualified from the ballot.

"Our office certifies the candidates to the county clerks on April 24," Thomas said.

The check bounce comes as no surprise as Gingrich confirmed a debt of almost $4.5 million to ABC News on Tuesday. The last Federal Election Commission report from February showed a debt of less than $2 million.

Gingrich told ABC News today that the debt increase was because the campaign got "very excited in Florida" after his South Carolina win.

"Romney spent $20 million in Florida in three weeks and I think some of our guys decided to try to match him and we didn't have Wall Street," Gingrich said. "I am going to spend some time paying it off. It is something I have done several times in my career."

Gingrich said his campaign did "exactly what a conservative should do" who is in debt.

"We cut our expenses, we cut our staff, we are now in the process of paying it off but I think what happened is, they got really involved in the fight in Florida and didn't stop and just say to themselves, 'Wait a second.' I can beat Mitt Romney in ideas, I can't possibly compete with him in money," Gingrich said.

On the day Rick Santorum suspended his campaign, Gingrich sent an email to supporters saying he was "the last conservative standing." The campaign emailed to voters that the goal was to achieve 12,000 donations by midnight.