South Carolina businessman Gregory Brown, who lost the Democratic primary to House Majority Whip James Clyburn (S.C.) on Tuesday, reported a spending deficit of approximately $88,000, according to campaign finance reports filed this week.

Clyburn called Thursday for state and federal authorities to probe whether Brown, as well as newly minted South Carolina Senate nominee Alvin Greene, were recruited and funded as plants in the state’s Democratic primary.

According to three reports Brown filed, his campaign reported negative cash on hand at the end of both the first and second quarters of 2010, totaling negative $35,164 and negative $53,205, respectively. An amended second-quarter report listed no debts, however, only a negative cash balance.

Brown’s financial reports show almost $24,000 in payments to Stonewall Strategies for marketing. Preston Grisham, former campaign manager for Republican Rep. Joe Wilson of South Carolina, now operates a firm by the same name in the Palmetto State.

But Brown’s campaign also paid the Charleston-based firm WGG Consulting nearly $7,100 for consulting work. South Carolina State Rep. Wendell Gilliard (D) owns a firm that bears the same name.

The campaign also listed payments to the state Democratic Party totaling nearly $4,700 for “vote builder” and “candidate registration” in April.

Other major expenditures included payments totaling $12,000 to Glenn Manning for campaign management and consulting in March and April. A firm named the Glenn Manning Law Offices shares the address listed in Brown’s filings.

Brown reported raising $400 in the first quarter and $835 in the second quarter.