WASHINGTON -- Susan E. Rice was playing stand-in on the morning of Sept. 16 when she appeared on all five Sunday news programs, a few days after the deadly attack in Benghazi, Libya, that killed four Americans.
Secretary of State Hillary Rodham Clinton would have been the White House's logical choice to discuss the chaotic events in the Middle East, but she was drained after a harrowing week, administration officials said. Even if she had not been consoling the families of those who died, including Ambassador J. Christopher Stevens, Mrs. Clinton steers clear of the Sunday shows.
So instead, Ms. Rice, the ambassador to the United Nations, delivered her now-infamous account of the episode. Reciting talking points supplied by intelligence agencies, she said that the Benghazi siege appeared to be a spontaneous protest rather than a premeditated terrorist attack. Within days, Republicans in Congress were calling for her head.
In her sure-footed ascent of the foreign-policy ladder, Ms. Rice has rarely shrunk from a fight. But now that she appears poised to claim the top rung -- White House aides say she is President Obama's favored candidate for secretary of state -- this sharp-tongued, self-confident diplomat finds herself in the middle of a bitter feud in which she is largely a bystander.
"Susan had a reputation, fairly or not, as someone who could run a little hot and shoot from the hip," said John Norris, a foreign-policy expert at the Center for American Progress. "If someone had told me that the biggest knock on her was going to be that she too slavishly followed the talking points on Benghazi, I would have been shocked."
At the United Nations, and in posts in the Clinton White House, Ms. Rice, who turned 48 on Saturday, has earned a reputation as a blunt advocate, relentless on issues like pressuring the regime in Sudan or intervening in Libya to prevent a slaughter by Col. Muammar el-Qaddafi.
She was a Rhodes scholar, has degrees from Stanford and Oxford, a Rolodex of contacts and a relationship with Mr. Obama sealed during his 2008 campaign. So her ascension to lead the State Department would be less a blow for diversity -- she would, after all, be the second black woman named Rice to hold the job -- than the natural capstone to a fast-track career.
Yet the firestorm over Benghazi raises more basic questions: Is Ms. Rice the best candidate to succeed Mrs. Clinton as the nation's chief diplomat? Does she have the diplomatic finesse to handle thorny problems in the Middle East? And even if Mr. Obama gets the votes for her confirmation, has the episode so tainted her that it would be hard for her to thrive in the job?
Ms. Rice's supporters say she has compiled a solid record at the United Nations, winning the passage of resolutions that impose strict sanctions on Iran and North Korea. Diplomats praise her for re-engaging with the institution after deep strains during the George W. Bush administration. But even those who back her tend to emphasize factors like her ties to Mr. Obama, an advantage that Mrs. Clinton, for all her celebrity, did not have.
"Given that he's probably the most withholding president on foreign policy since Nixon, if anyone can get him to delegate, not dominate, it's Rice," said Aaron David Miller, a longtime Middle East negotiator now at the Woodrow Wilson Center. "That would be good for her, and for our foreign policy."
While some in the State Department are wary of her, recalling her stormy tenure as assistant secretary for African affairs in the Clinton administration, Ms. Rice has a core of support among Mr. Obama's aides, particularly those who worked with her on the 2008 campaign. They insist that Benghazi will not derail her chances. Some analysts said Mr. Obama's defense of her at a news conference last week was so impassioned that he had left himself little room to put forward an alternative, like Senator John Kerry of Massachusetts.
Still, other longtime Washington observers question if Mr. Obama would risk a battle over his secretary of state when he needs to cut a deal with Republicans on the budget and taxes.
Certainly, the vitriol between him and Senator John McCain, who charged last week that Ms. Rice had misled the public and called her "not qualified" for the State post, suggests that a confirmation vote for her would be a toxic affair. She has other powerful defenders, like Senator Dianne Feinstein, the California Democrat and chairwoman of the Senate Intelligence Committee, who said that Ms. Rice had done nothing wrong and was a victim of character assassination.
Ms. Rice, who has kept a low profile since her TV appearances, did not comment for this article.
"The attacks are patently unfair and mean-spirited," said Tommy Vietor, a spokesman for the National Security Council. "Susan's record at the U.N. is exceptional." He added that Ms. Rice, who was an early supporter of Mr. Obama's and advised him on foreign policy, is in addition a longtime friend of the president.
A scrappy point guard in high school -- she was also valedictorian at the National Cathedral School -- Ms. Rice is one of several basketball players in Mr. Obama's inner circle. He and his wife, Michelle, recently invited Ms. Rice and her husband, a Canadian-born television producer, Ian Cameron, to the White House for a celebratory, post-election dinner with Gov. Deval Patrick of Massachusetts and other friends.
Even before those invitations, Ms. Rice had an entree to elite Washington. The daughter of Emmett J. Rice, a governor in the Federal Reserve System, and Lois Dixon Rice, an education policy expert, Ms. Rice spent her childhood mixing with family friends like Madeleine K. Albright, another secretary of state.
At 28, she was an aide in President Bill Clinton's National Security Council, where she once questioned embracing the term "genocide" in Rwanda because it could put Mr. Clinton in an awkward position in midterm elections. At the State Department, diplomats recall her lecturing leaders in Africa decades her senior.
As a campaign surrogate in 2008, Ms. Rice could be withering. When Mr. Obama made a trip to the Middle East, she mocked an earlier visit Mr. McCain had made to a market in Baghdad, in which he wore body armor. "I don't think he'll be strolling around the market in a flak jacket," she said of her candidate.
Ms. Rice's relationship to Mrs. Clinton also began on chilly terms, officials said, in part because Ms. Rice embraced Mr. Obama's candidacy rather than Mrs. Clinton's. In the early days of the administration, one former aide said, their offices would occasionally issue competing statements on the same topic.
But over time, representatives of both women say, they have developed a good rapport. They see plenty of each other, with Ms. Rice keeping an office at the State Department and commuting between New York and Washington, where she and Mr. Cameron have two children.
In New York, Ms. Rice has had little use for the bland artifice of diplomatic language. When Russia and China blocked a resolution condemning the crackdown in Syria, Ms. Rice wrote on Twitter, "Disgusted that Russia and China prevented the U.N. Security Council from fulfilling its sole purpose." At the White House, she tangled with Mr. Obama's special envoy to Sudan, J. Scott Gration, and became so immersed in that country's looming split that subordinates termed her the "Sudan desk officer."
By her own account, Ms. Rice's fervor is fueled by the Clinton administration's inaction in Rwanda. Years later, she told Samantha Power, then a journalist writing about the episode, that "I swore to myself that if I ever faced such a crisis again, I would come down on the side of dramatic action, going down in flames if that was required."
Last year, working with Ms. Power (now herself in the National Security Council), Mrs. Clinton, and other officials, Ms. Rice helped persuade the president to back NATO military intervention in Libya.
In some ways, friends say, Ms. Rice's appearance on the Sunday shows underlines how she has evolved from a headstrong young staffer into a disciplined senior member of Mr. Obama's team.
"She's really tough, but there is a difference in how she's tough," said Harold H. Koh, the State Department's legal adviser. "During the Clinton administration, there was a feeling that she had to be tough to earn her place at the table. Now she's more comfortable."
This article originally appeared in The New York Times.