WASHINGTON (AP) June 7, 2008 - Hillary Clinton today ended her presidential campaign with a call for her those who backed her to unite behind former rival Barack Obama.

In a speech to supporters at the National Building Museum in Washington, Clinton congratulated Obama saying, "I endorse him and throw my full support behind him."

With her unqualified endorsement, Clinton pivoted from her role as determined foe to absolute ally of the first black to secure a presidential nomination.

As recently as Tuesday, the former first lady continued to cast herself as the candidate best able to defeat Republican nominee-in-waiting John McCain.

Obama, who had enough delegates to clinch the nomination after Tuesday's primaries in South Dakota and Montana, planned to spend the weekend at home in Chicago.