What are facts about Hillary Clinton?

She is the first (and thus far, the only) former First Lady to become a US senator. She was Barack Obama's rival in the 2008 presidential race, when she tried unsuccessfully to become the Democratic nominee. She lost out to Mr. Obama in a very bitter contest. But after he was elected president, he chose her to be his Secretary of State and they put their rivalry behind them. She served one term as the head of the State Department, visiting more than 100 countries and being praised for her skill as a diplomat. At the end of four years, she asked to step down, and she was replaced in President Obama's second term by Senator John Kerry.