WASHINGTON - Susan Rice, the US ambassador to the United Nations, has emerged as the favoured candidate to succeed Secretary of State Hillary Clinton, even with the political controversy over her remarks about the Sept 11 attack on the American diplomatic mission in Benghazi, Libya, according to media reports.

But she and the other candidate on President Barack Obama’s list - Senator John Kerry - for the most coveted cabinet post are dogged by issues that could complicate their path to Mrs Clinton’s State Department office, according to The New York Times.

Of the two, Ms Rice, an outspoken, ambitious diplomat with close ties to Obama, has emerged as the clear favourite, the newspaper said. But she would face stiff resistance on Capitol Hill, where she has come under withering criticism from Republicans for asserting that the deadly attack on the American mission in Benghazi, Libya, might have been a spontaneous protest rather than a terrorist attack.

Kerry, who is the chairman of the Senate Foreign Relations Committee and prepped Obama for his debates with Mitt Romney, his Republican rival, holds a Senate seat that the White House worries could fall into Republican hands if he gave it up for a cabinet post.

Both Ms. Rice and Kerry have a reservoir of good will in the Oval Office, and if she gets the nod, officials said, Kerry could be considered for defense secretary. But politics will inevitably play a part in Obama’s decision, especially in the wake of the sex scandal that brought down David Petraeus as director of the Central Intelligence Agency.

The decision, administration officials said, will likely hinge on whether Obama would risk a bruising confirmation battle for Ms. Rice or the loss of Kerry’s seat, which could be picked up by Scott Brown after the loss of his own seat last week.

“The question is, does the president want to launch a major fight with Congress over his choice of secretary of state?” said Aaron David Miller, a longtime diplomat who is vice president of the Woodrow Wilson International Center for Scholars.

The Senate and House have scheduled hearings on Benghazi this week, which will keep the heat on Ms Rice as the White House begins its deliberations. At least one influential Republican, Senator Lindsey Graham of South Carolina, has already come out against her. “I’m not entertaining promoting anybody that I think was involved with the Benghazi debacle,” Graham said Sunday on “Face the Nation” on CBS. “Susan Rice needs to be held accountable.”

The White House stoutly defends Ms Rice, noting that in her remarks on Benghazi, she was reading from a briefing prepared by the intelligence agencies. The administration, citing new evidence, subsequently confirmed that the attack was an act of terrorism.

“Anyone who opposes Susan, based on one day’s comments, will have to reconcile that with what the intelligence said on that day,” said an administration official, speaking on condition of anonymity. In the unforgiving climate of Washington, though, Kerry might profit from Ms Rice’s misfortune, according to the Times.

He would likely breeze through a confirmation hearing with his Senate colleagues. And he has been a loyal soldier for the administration on a variety of issues. In 2009, the White House dispatched Kerry to Afghanistan, where he helped talk President Hamid Karzai into accepting a runoff election. In the Senate, Kerry has pushed for Obama initiatives like the New Start treaty with Russia.

Kerry also involved in the negotiations leading to the release of Raymond David, who was responsible for killing two Pakistanis in Lahore.

With his patrician bearing and Massachusetts roots, he was an obvious stand-in for Romney during debate preparation. While the president’s lackluster first debate almost capsized his campaign, his aides said they did not blame Kerry.

Nor does the loss of his Senate seat appear quite as problematic as it did before last Tuesday. Senator Brown, who was defeated by Elizabeth Warren, left the door open to another run. But some political analysts in Massachusetts say he might be more inclined to run for governor, given that the state once elected a fiscally conservative, socially moderate Republican - Romney - to that post. Even if he did run for the Senate, Brown would face a robust bench of Democrats.

“I think the administration could feel relatively confident that they will hold on to the seat,” said Thomas Whalen, a political historian at Boston University. “When you look back on Brown, it was a special election against an exceptionally weak Democratic opponent.”

Weighing against Kerry, officials said, is that he would be replaced as chairman of the Foreign Relations Committee by Senator Robert Menendez of New Jersey. With his Cuban roots and hostility toward the Castro regime, Menendez would likely impede any diplomatic overture by Obama.

Mrs Clinton has long insisted that she would not serve during a second term, but she recently left open the possibility of staying on the job long enough for a successor to win confirmation. That could allow the White House to delay Ms Rice’s nomination to allow the passions over Benghazi to subside, the report said.