The presidential campaign of Rick Santorum ended with $2.2 million in debts and only $1 million cash on hand, according to a report filed with the Federal Election Commission on Sunday.

That amount of debt is up $300,000 from the $1.9 million the Santorum campaign reported at the end of March. The report for March was filed just 10 days before Santorum suspended his campaign citing a lack of funds to keep going. He had $1.8 million cash on hand at the time.

Santorum's unexpected string of victories put a strain on his limited organization as he tried to compete with the well-financed machine run by Mitt Romney. The big spending from the pro-Romney super PAC, Restore Our Future, put further pressures on Santorum's campaign.

Santorum's campaign raised $1.2 million in April and spent $2 million as it wound down. The campaign spent $965,498 in the first 10 days of the month before Santorum stepped out of the race and an additional $1.1 million after he exited.

The debt racked up by Santorum still pales in comparison to the $4 million-plus run up by fellow Republican presidential candidate Newt Gingrich.

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