GMAC Financial Services, the General Motors Corporation (GM) financing unit that received a $6 billion infusion from the government earlier this week, said Wednesday it raised $21.2 billion in a debt-for-equity swap designed to increase its available capital and allow it to become a bank holding company under U.S. government rules. The lender said holders of $21.2 billion of debt will swap their stakes for $15.7 billion of new securities plus cash. The exchange will ease GMAC's debt burden, though the lender fell short of its goal of 75 percent participation in the $38 billion swap, instead getting about 56 percent. GMAC said it raised $17.5 billion from debt holders, while its home-loan branch, Residential Capital, raised $3.7 billion. The company's offer required investors to accept less than face value for their holdings. It was designed to enable GMAC to become a bank holding company, allowing it to receive low-cost funding and helping to assure its survival. Wednesday's announcement came after GMAC was promised a total of $6 billion in assistance from the Treasury Department. That would bring the total amount of cash raised or promised to $27.2 billion—$2.8 billion below the $30 billion needed for the lender to become a bank holding company.