Deal to make BofA No. 1 in mortgages

While risky, Bank of America's acquisition of hobbled lender Countrywide Financial would expand its role as the dominant U.S. consumer bank, adding mortgages to its top positions in deposits and credit cards.

The Charlotte bank confirmed Friday that it is buying the nation's biggest mortgage lender for $4 billion in stock. The bank, which has gobbled up scores of rivals over the years, has consistently said size is an advantage that lets it reach more customers, develop better products and cut expenses.

The purchase is also a mission to rescue a key player in the mortgage industry and the $2 billion investment the bank made in the Calabasas, Calif.-based lender in August.

Bank of America chief executive Ken Lewis' purchase is a gamble because the mortgage business has been battered by rising defaults amid the worst housing slump in decades. read more