Debo Adegbile had been nominated by President Obama to become the next Assistant Attorney General for the Civil Rights Division at the Department of Justice, but the nomination was blocked. (Alex Wong/Getty Images)

The Senate on Wednesday dealt an embarrassing setback to President Obama when several politically vulnerable Democrats defected to help Republicans defeat the nomination of Debo P. Adegbile to be chief of the Justice Department’s Civil Rights Division.

Adegbile’s nomination had revived the racially charged legacy of the murder of a Philadelphia police officer more than three decades ago — a case in which, long after the trial, Adegbile played a small role — and the vote exposed the anxiety facing many red-state Democratic senators as the midterm elections approach.

Seven Democrats joined with Republicans in blocking a final vote on the nomination, the largest number of Democrats to vote against an Obama nominee, according to Senate aides. Adegbile’s ties to the case of Mumia Abu-Jamal, an internationally known prisoner convicted of the 1981 murder of Officer Daniel Faulk­ner, had become the focus of a conservative crusade that boiled over in recent weeks.

A senior aide to one of the senators who voted against the nominee said several senators’ offices were “very angry” at the White House for moving ahead with the nomination even though it could leave Democrats who are facing tough reelection races vulnerable to attack ads.

“It’s a vote you didn’t have to take. It’s a 30-second ad that writes itself,” said the aide, who spoke on the condition of anonymity in order to speak frankly.

Mumia Abu-Jamal, convicted of killing Philadelphia police officer Daniel Faulkner in 1981, leaves a Philadelphia court on July 12, 1995. (CHRIS GARDNER/AP)

Administration officials pushed back late Wednesday, saying that Senate Majority Leader Harry M. Reid had assured the White House on Tuesday evening that Adegbile would survive the procedural vote, if only by a slim margin. At that point, at least two Democratic senators who voted no had been expected to vote to proceed, but they flipped their votes Wednesday under pressure from other wary Democrats, according to a senior administration official familiar with the process but not authorized to speak publicly on the matter.

The vote was expected to be close, and Obama and Vice President Biden had lobbied Democrats for their support in recent days, according to aides. Biden also was on hand Wednesday to cast a tie-breaking vote if needed. But only 47 senators voted to proceed to final consideration of Adegbile, making him the first Obama nominee rejected since Democrats changed Senate procedure last year to require a simple majority of senators present to advance a nominee to a final vote. Even though they knew they had no GOP support, Democrats brought the nomination to a vote because they were betting that enough of their own would stick with the president.

“We were very close to getting this good man nominated,” Reid (D-Nev.) told reporters after the vote. Adegbile’s fate was sealed, he said, “when a number of people saw the vote not going in a certain way.”

Reid had spoken in defense of Adegbile and initially voted in favor but later switched his vote to no, making him the eighth Democrat to vote against the nominee. But Reid did so only to reserve his right as Senate leader to bring up the nomination again. Later Wednesday, aides couldn’t say whether that will happen.

Adegbile, 47, spent more than a decade working for the NAACP Legal Defense Fund, where he served as the group’s in-house voting rights expert. His defenders note that the Legal Defense Fund began its work on Abu-
Jamal’s behalf before Adegbile’s tenure began but acknowledge that he contributed to the filing of a 2009 court brief that argued that Abu-Jamal faced a discriminatory jury — an appeal found to have merit by a judge.

It was that involvement that inspired Adegbile’s opponents, including Faulkner’s widow, to argue that he should be disqualified from holding any publicly appointed position in the justice system.

“Today is a good day for Pennsylvania, for America, and for those who believe in justice,” said Sen. Patrick J. Toomey (R-Pa.), who led the opposition to Adegbile’s nomination and read a letter from Faulkner’s widow on the Senate floor. “The Senate affirmed that our criminal justice system must never be abused to propagate a dishonest, radical agenda. The American people, especially law enforcement and Maureen Faulkner, deserve better.”

The decision by seven Democrats to buck their party leadership and the White House caused a rare split in the Senate Democratic Caucus, which has been unified in supporting Obama’s nominees.

In a statement, Obama said the vote had “denied the American people an outstanding public servant.”

Attorney General Eric H. Holder Jr., who has said he plans to make tackling civil rights issues his major focus during the remainder of Obama’s term, said he was disappointed by the vote.

“It is a very dangerous precedent to set for the legal profession when individual lawyers can have their otherwise sterling qualifications denigrated based solely on the clients that their organizations represent,” Holder said in a statement.

The Senate Democrats who opposed the nominee were: Christopher A. Coons (Del.), Robert P. Casey Jr. (Pa.), Mark Pryor (Ark.), Heidi Heitkamp (N.D.), Joe Manchin III (W.Va.), Joe Donnelly (Ind.) and John Walsh (Mont.).

Pryor faces one of the most difficult reelection battles of any Democrat this year, while Donnelly, Heitkamp, Manchin and Walsh hail from socially conservative states that Obama lost in 2012.

“I made a conscientious decision after talking to the wife of the victim,” Manchin told reporters after the vote.

As a member of the Senate Judiciary Committee, Coons voted to refer Adegbile to the full Senate. But in a statement Wednesday, he said he voted in opposition out of concern that Adegbile “would face such visceral opposition from law enforcement on his first day on the job.” Coons also represents a state near Philadelphia where the Abu-Jamal case is well known.

For several of the Democrats who supported Adegbile and face difficult reelection campaigns, the vote was potentially damaging.

Within hours, state Republican parties began unloading. The New Hampshire GOP targeted Sen. Jeanne Shaheen in a statement titled “Shaheen votes for radical Obama nominee who defended unrepentant cop killer.” The North Carolina Republican Party issued a statement saying, “Kay Hagan Votes For Extremist DOJ Nominee Who Helped Get A Convicted Cop Killer Off The Hook.”

The vote appeared to be a miscalculation by the White House and Senate Democrats, who have worked together for years to deflect GOP opposition to Obama’s picks and usually vote in lock step to confirm his nominees. Democratic leaders also have avoided holding controversial votes this year, focusing instead on modest proposals designed to bolster the chances of Pryor, Hagan, Sen. Mary Landrieu (La.) and others who are expected to face millions of dollars in attack ads by Republicans and outside conservative groups.

Voting in favor of Adegbile is unlikely to cause much trouble for Sen. Mark Begich (Alaska), who enjoys a 60 percent job approval rating and has been a staunch opponent of Republicans who block Obama’s nominees. But the vote probably will not help Hagan and Landrieu, who have the dual challenges this year of rallying large African American voting blocs and finding ways to appeal to centrist white swing voters.