Martin O'Malley endorses Hillary Clinton for president on May 9, 2007.
O'Malley flashback: The 2007 Clinton endorsement
In May 2007, then-Gov. Martin O'Malley wholeheartedly endorsed Hillary Clinton for president. Now, he's planning his own presidential run against her.
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Meet Martin O'Malley 19 videos
Martin O'Malley endorses Hillary Clinton for president on May 9, 2007.
O'Malley flashback: The 2007 Clinton endorsement
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JOHNSTON, IA - JANUARY 31: Democratic Presidential Candidate Martin O'Malley speaks to potential supporters at a residence on January 31, 2016 in Johnston, Iowa. O'Malley and other candidates are making their final appeals to voters ahead of the Iowa caucus February 1. (Photo by Steve Pope/Getty Images)
Sources: Martin O'Malley to suspend campaign
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JOHNSTON, IA - JANUARY 31: Democratic Presidential Candidate Martin O'Malley speaks to potential supporters at a residence on January 31, 2016 in Johnston, Iowa. O'Malley and other candidates are making their final appeals to voters ahead of the Iowa caucus February 1. (Photo by Steve Pope/Getty Images)
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O'Malley accuses DNC of stacking deck for Clinton
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O'Malley booed for saying "All lives matter"
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Opening night at the Horseshoe casino, in Baltimore, MD. August 26, 2014.
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O'Malley slams Obama for border crises
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O'Malley strikes contrast with Clinton on justice reform
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Martin O'Malley on Baltimore residents blaming him
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Can this Democrat really beat Hillary Clinton?
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Former Democratic Maryland Governor Martin O'Malley addresses the 2015 International Association of Fire Fighters (IAFF) Alfred K. Whitehead Legislative Conference and Presidential Forum in Washington, D.C., March 10, 2015.
Martin O'Malley announces presidential run
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