As US secretary of state, Clinton is the first former first lady to serve in a president's cabinet. In the renewed Middle East peace talks, she faces her greatest challenge since accepting the job following her doomed presidential bid in 2008. She insists that the US "cannot and will not impose a solution". Meanwhile, ahead of the 2012 election, there is growing talk of her replacing the gaffe-prone vice-president, Joe Biden, as Barack Obama's running mate.
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