What is certain is that Clinton does not intend to serve in Obama's second term.

"I think after 20 years, and it will be 20 years, of being on the high-wire of American politics and all of the challenges that come with that, it would be a -- probably a good idea to just find out how tired I am," she said in an interview with CNN earlier this year about stepping down even if Obama was re-elected.

"I'm aiming to leave shortly after the inauguration; that's my plan," she told the Washington Post in an interview a week before Obama won a second term. "I'm not really open to staying longer, but I also know that we have to be conscious of the work that has to be done. And again, I'll have to talk to the president."

Her spokesman later said she would stay until a new secretary of state is confirmed, a common practice for outgoing Cabinet members.

But the prospect of who will fill her shoes has become a more complicated question in recent days.

Speculation has centered on Susan Rice, who currently serves as the U.S. Ambassador to the United Nations, as the most likely candidate to be nominated by Obama. But her explanation of the administration's response to the Benghazi attack has come under intense criticism by Senate Republicans who would ultimately vote on any nominee.

"Let's see what happens here, but we will do what ever is necessary to block the nomination that's within our power as far as Susan Rice is concerned," Sen. John McCain (R-Ariz.) said at a press conference last week. Just this week, 97 House Republicans sent a letter to the president declaring their opposition as well.

It is still a guessing game as to precisely when Clinton will announce her resignation. She is thought to want to remain on the job at least until a congressionally ordered investigation of the Benghazi incident is completed.

Regardless of what happens, she has made it clear that her time as America's top diplomat is coming to a close, and with it, a long career on the national stage who's every movement seemed to garner scrutiny across a range of issues.

In an interview during a trip to India with CNN's Jill Dougherty earlier this year, Clinton seemed to be looking to her coming retirement when she was asked about how her appearances were being discussed in the blogosphere.

"I feel so relieved to be at the stage I'm at in my life right now, Jill, because if I want to wear my glasses, I'm wearing my glasses. If I want to pull my hair back, I'm pulling my hair back. And at some point it's just not something that deserves a whole lot of time and attention, and if others want to worry about it, I'll let them do the worrying for a change."