Of the big U.S. banks, Jamie Dimon’s is the only one that didn’t turn in a losing quarter during the financial crisis. Recovery is bringing stronger results: J.P. Morgan Chase posted record profits in 2010.Chase is working on consolidating its lead this year. For the first time, it’s poised to surpass both Goldman Sachs and Morgan Stanley in the lucrative M&A business. And in the biggest sign yet that credit markets have thawed, J.P. Morgan extended a one-year, $20 billion bridge loan to AT&T for its $39 billion purchase of T-Mobile, the bank’s biggest single loan commitment ever. —P.N.