White House Chief of Staff Jack Lew will be nominated for Treasury secretary by President Obama Thursday, according to several news sources.

If confirmed by the Senate, Lew would replace Timothy Geithner, who has said he doesn't wish to serve a second term and will leave the post by Jan. 31.

Lew served under both Obama and President Bill Clinton as director of the Office of Management and Budget. In between administrations, he worked as chief operating officer of Citigroup's Alternative Investments unit, where he oversaw a successful hedge fund investment that predicted the collapse of the housing market.

If confirmed, Lew will face the immediate task of working with Congress to raise the federal government's $16.4 trillion debt ceiling after the statutory limit was reached on Dec. 31. Lew may also weigh in on tax reform as the House is expected this year to consider new ways to increase federal revenue.

Geithner and the Obama Administration have stated that they support the credit union tax exemption. Geithner also weighed in on the extension of the transaction account guarantee extension sought by banks last year, saying he opposed the continued deposit coverage. That bill failed to pass the Senate.

According to NAFCU, Lew voiced support for credit unions providing capital to small businesses during a May 2012 visit to the White House to discuss member business lending legislation with Obama's Administration.

Candidates reported likely to fill Obama's open chief of staff position include Deputy National Security Adviser Denis McDonough and Ron Klain, who was formerly Vice President Joe Biden's chief of staff.