As Hillary Clinton prepares to step down as secretary of state, U.N. Ambassador Susan Rice announced she is withdrawing her name as a possible replacement.
Now the search is on for who will fill the top spot, along with other cabinet openings.
Rice once seemed a shoo-in for secretary of state, but controversy over her explanation for the attack on the U.S. Consulate in Benghazi, Libya, compromised her candidacy.
On Thursday, the U.N. ambassador announced she no longer wanted the job.
"The position of secretary of state should never be politicized. I am saddened that we have reached this point even before you have decided who to nominate," she wrote in a letter to President Obama.
Rice came under criticism by Republicans for her initial analysis of the deadly attack on the consulate in Libya. She repeatedly blamed protests over an anti-Muslim film when many suspected it was a planned terror attack.
"We are significantly troubled by many of the answers that we got and some that we didn't get," Sen. John McCain, R-Ariz., said of Rice's congressional testimony.
Her exit leaves an opening for Sen. John Kerry, D-Mass.
Kerry, who unsuccessfully sought the presidency in 2004, has vaulted to the top of the president's short list of possible candidates.
The Massachusetts lawmaker is noted for his foreign relations experience and relationship building skills that could help him succeed as the country's top diplomat.
Other Cabinet Nominees
Rounding out the cabinet is Nebraska Republican Sen. Chuck Hagel, who has emerged as the front runner to replace exiting Secretary of Defense Leon Panetta.
The possible selection of Kerry and Hagel would put two decorated Vietnam War veterans -- one Navy, the other Army -- at State Department and the Pentagon.
There's also an opening for the top job at the CIA -- acting Director Michael Morell and White House counter-terrorism adviser John Brennan are contenders.
Meanwhile, a Kerry nomination could mean a vacant Senate seat and a special election in Massachusetts. Outgoing Sen. Scott Brown, R-Mass., is viewed as a strong contender to fill the spot.
The president has made it clear that Rice will stay on as U.N. ambassador and remain a key member of his cabinet and national security team.