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In an exclusive statement to ABC News, Richardson said after speaking with former President Bill Clinton and his wife, "we have patched up our disagreement from the 2008 election." The former governor, who served in Clinton's administration, gave his endorsement to then Sen. Barack Obama during the 2008 campaign cycle.
“I have spoken to President and Secretary Clinton and we have patched up our disagreement from the 2008 election,” the statement read. "I am pleased to announce I wholeheartedly support Secretary Clinton's candidacy for the Presidency. Her leadership on issues like foreign policy, immigration, climate change and economic populism are important to the future of the country."
Clinton welcomed Richardson's endorsement Monday morning, saying she was "grateful" for his support.
"I thank Governor Bill Richardson for his endorsement,” Clinton said in a statement. “For more than three decades, Bill has worked doggedly to make our country and our world more equal, safe, and free. Through his many years of public service, Bill has been a good friend to me and an unerring friend to the American people. I am grateful for his trust and his support.”
An earlier version of this story misidentified the president with whom Richardson spoke before endorsing Hillary Clinton. It was former President Bill Clinton, not President Obama.