President Obama is expected to unveil White House Chief of Staff Jack Lew as his treasury secretary nominee Thursday, tapping a budget wonk with deep ties in Washington but also someone who antagonized Republicans during contentious fiscal negotiations.

With the exit of Treasury Secretary Timothy Geithner in coming weeks, Lew, if confirmed, would take over the Treasury Department in the middle of a battle between the White House and Congress about how to raise the $16.4 trillion debt ceiling. Multiple sources with knowledge of Lew's appointment confirmed his selection to The Washington Examiner.

Obama had hoped the opening days of his second term would be devoted to fiscal issues and other items at the top of his agenda, such as gun control and immigration. However, with the nominations of Lew, former Sen. Chuck Hagel, R-Neb., for secretary of defense and counterterrorism adviser John Brennan to lead the CIA, the makeup of Obama's Cabinet could overshadow other issues.

Even without formally acknowledging the selection of Lew, the White House looked to ease his path to confirmation Wednesday.

Obama spokesman Jay Carney called Lew the rare Washington figure who had "earned the admiration of almost everybody that he's worked with," citing Lew's focus on Social Security reform under Republican President Reagan and balancing the budget during Democrat Bill Clinton's presidency.

But some Republicans scoffed at that depiction of the man they dealt with during heated negotiations about averting the so-called fiscal cliff.

"Jack Lew must never be Secretary of Treasury," Sen. Jeff Sessions, the top Republican on the Senate Banking Committee, said in a statement. "At this time of unprecedented slow growth, high unemployment and huge deficits, we need a Secretary of Treasury that the American people, the Congress, and the world will know is up to the task of getting America on the path to prosperity not the path to decline. Jack Lew is not that man."

And though Carney on Wednesday vowed Obama "will not negotiate over the debt ceiling," some analysts said Republicans would use the Lew hearing as leverage to extract spending cuts in exchange for raising the nation's borrowing capacity.

"They would be foolish not to use this opportunity to lay the foundation for their strategy on the debt ceiling," said Larry Sabato, a political scientist at the University of Virginia. "That's a high-profile hearing that they don't want to let go to waste."

Lew led the Office of Management and Budget under both Obama and Clinton. In addition to the debt ceiling, Lew would play a major role in navigating deep spending cuts to military and domestic programs scheduled for March. He'd then be a critical player in attempting to craft a deal with Congress to keep the government operating later that month.

For Obama, handing the reins to Lew, the head figure of his inner circle, ensures that the Treasury Department will serve as an extension of the White House in difficult battles with Republicans.

But some analysts said they prefer someone whose politics weren't so closely aligned with Obama's.

"He's an insider; he's an obvious choice," Dean Baker, co-director of the Center for Economic and Policy Research, said of Lew. "But I'm not terribly happy. He's more of the same. The economy isn't exactly growing at a fast pace right now."