It was a bad pick for many reasons

How Mumia Abu-Jamal doomed Debo Adegbile in the Senate

The nomination angered some Democrats, who noted that the vote placed vulnerable Democratic Senators in the middle of the decades-long tug-of-war over control of Abu-Jamal’s legacy between the law enforcement community and civil rights groups. That consternation only grew after the nomination failed, meaning some vulnerable Democrats had walked a political plank for not much.
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Democrats representing red states and up for reelection in 2014 were stuck in the miserable position of choosing between defecting from their caucus by opposing an Obama nominee or voting for Adegbile and facing the potential that they would face campaign ads that alleged they supported someone who defended a cop-killer hit the airwaves. In the words of one Democratic aide: “It’s a 30-second ad that writes itself.”