In choosing Mr. Allison to head the Troubled Asset Relief Program, the administration is turning to an experienced manager at a time when it is having trouble filling key finance posts. Mr. Allison, 65 years old, is the former chairman of investment company TIAA-CREF and was a Merrill Lynch & Co. executive for years. In September, he agreed to run Fannie Mae after the U.S. took over the mortgage giant and its sister firm, Freddie Mac.

Mr. Obama could announce his intention to nominate Mr. Allison as assistant secretary for the Office of Financial Stability as early as this week. Mr. Allison would replace Neel Kashkari, a holdover from the Bush administration, who was asked by Treasury Secretary Timothy Geithner to stay on until a replacement was found.

The selection will leave the administration searching for permanent leaders of both Fannie and Freddie.