Wholesale lenders drove the subprime mortgage market to its best year ever in 2004, a new Inside B&C Lending analysis reveals. But 2005 could see retailers regain some lost ground. Inside B&C Lending estimates that mortgage brokers and correspondents, on a combined basis, accounted for 72.4 percent of the $529.9 billion in new B&C loans generated last year. That was up significantly from 2003, when 65.5 percent of total volume came from wholesale channels.…