The post-financial crisis era will forever be known as the “Ben Bernanke age” as defined by near zero interest rate policies, quantitative easing and pushback from upset lawmakers and citizens.

But it’s clear that Bernanke’s hawkish commitment to buying mortgage-backed securities turned him into one of the most historic Fed leaders since the central bank’s inception. 

Love Bernanke or hate him, his presence is a hard one to replace, and the list of potential replacements is just as controversial as the chairman’s long-term commitment to QE3.

In the lead is Janet Yellen, vice chair of the Board of Governors for the Federal Reserve System. Right now, analysts see her as Obama's top pick for a Bernanke replacement.

"If I was a betting man, my money would be on Yellen," said Mark Calabria with the Cato Institute. "The president is going to look for someone who is not going to spook the markets. It’s not a nomination that you’re going to go big and bold on. I really think there is going to be an emphasis on who is currently on the board or has been on the board."

Yellen would be the obvious pick since she is already a Federal Reserve Board Governor – and a party who has sat elbow-to-elbow with Bernanke, giving her insight as to where the Fed has been and where it’s going.

"I think it does seem as if Janet Yellen continues to be generally viewed as the favorite, with the next most likely being Larry Summers," added Ed Mills, a government policy analyst with FBR Capital Markets. "There is a lot of support for Yellen, but I think there has been some concern about whether or not she is the right person for the job, although I have not heard a good reason supporting that."

But because of this reluctance, Larry Summers’ name continues to surface.

Summers, a former Harvard leader and Clinton's Treasury secretary, may face an uphill battle. Analysts say his background in the Clinton administration may have won Summers enemies in Congress – a potential challenge to his confirmation.

Summers – unlike Yellen – may have trouble getting confirmed, Calabria noted.

"He would lose as many as a dozen Democrat votes," he explained. "I am fairly certain that he would not be able to obtain the needed 60 votes."

In other words, Summers has alienated even parts of the president’s Democratic coalition.

Ed Mills, on the other hand, is not soured on Summers’ potential.

"I think if Summers is nominated, he will be approved," Mills added. "He is someone who has been approved in the past. Some members, who would rather have another candidate, will not want to be responsible for some of the power vacuum that would occur by not knowing who the next chairman will be."

Other names thrown into the hat include former Treasury Secretary Timothy Geithner; Alan Blinder, a former member of President Clinton’s Council of Economic Advisors and a former vice chairman for the Fed Board of Governors; Roger Ferguson, president and chief executive of TIAA-CREFF; and Christina Romer, former chair of the Council of Economic Advisers for the Obama administration.

Calabria said Romer’s potential is dampened by the president’s controversial stimulus, which occurred in the first part of his presidency. The stimulus promised a certain number of jobs, and fell short of its goals. 

"I think what Romer has going against her was the complete public relations disaster surrounding the stimulus," Calabria said.

As for what the markets want, they desire a smooth transition, which makes Yellen look like a preferred choice.

Calabria puts Paul Volcker on the wish list, but doubts it’s a possibility at this point in Volcker’s career.

"If Janet Yellen is chosen, the street will assume a continuation of Bernanke’s policies. If Summers or someone outside the Fed is chosen, there will be more questions," Mills points out.

One of the benefits of a Yellen appointment is that Bernanke has already laid out a light-touch plan, showing his willingness to buy mortgage bonds interminably, or at least until the Fed is satisfied with the economic recovery.

A Yellen appointment would suggest the Fed will continue along this trajectory, being cautious and waiting for the right moment to exit.

 Mills says that, early on, there will be many questions if anything done by an incoming Fed Chair suggests less committment to accommodation or a faster-than-expected escape from Bernanke's approach.