President Barack Obama and Senate Majority Leader Harry Reid learned a lesson in unintended consequences last Wednesday when the Senate opted against shutting off debate on the President’s nominee for the Civil Rights Division of the Department of Justice. The body voted 52-47 to continue debate on Debo Adegbile, who had a hand in an appeal on behalf of Mumia Abu-Jamal, who was convicted of murdering a police officer in Pennsylvania.

Last November, most Senate Democrats voted to eliminate the filibuster for nominations to the Executive Branch and non-Supreme Court Judicial Branch positions. As a result, to cut off debate on such nominees, only a simple majority of the Senators was needed for a cloture petition to pass, rather than 60, as was the case before. The former threshold allowed the Republicans to easily block the President’s nominees since Democrats have not enjoyed a 60-Senator majority since his first term. Without a 60-strong Caucus, the Democrats could squarely lay the blame for a blocked nomination at the Republicans’ feet.

Today, however, because of the rules change, that is no longer the case. Democrats were forced to choose, and a number of them voted against invoking cloture on Adegbile’s nomination. According to The Washington Post, Senator Chris Coons of Delaware, Senator Bob Casey of Pennsylvania, Senator Heidi Heitkamp of North Dakota, Senator Joe Donnelly of Indiana, Senator Mark Pryor of Arkansas, and Senator John Walsh of Montana voted against cloture. (Senate Majority Leader Harry Reid technically voted against cutting off debate, but only did so after it was clear that he would lose the vote. He did this because a Member who votes on the prevailing side of an issue may move to reconsider a vote, which would allow him to bring up the nomination again.)

This was undoubtedly a defeat for the President. According to USA Today, President Obama dismissed the rejection as a “travesty based on wildly unfair character attacks against a good and qualified public servant.” But he really can’t criticize too harshly since he’d be taking to task Members of his own party in the process. In voting against Adegbile, the Democratic Senators were saying either that he was a bad choice, or their constituents would fault them for voting for him, or both.

To the extent that they considered public opinion in this vote, it was undoubtedly a tough decision for the Democratic Senators who opposed the nomination. With the exception of Casey (and Reid), they are all vulnerable. In the 2012 election, Senator Heitkamp had a narrow victory, clinching 50.5 percent of the vote. Likewise, Senator Donnelly won less than a majority, with 49.9 percent of the vote. Senator Pryor is in a tough reelection fight, and the RealClearPolitics polling average at the time of this writing had him down by more than two points against challenger Representative Tom Cotton. Representative Steve Daines also has a slight advantage over his competitor Senator John Walsh. Senator Casey generally votes with his party, but Adegbile’s nomination undoubtedly struck a chord with Pennsylvanians.

Many Democrats are highly critical of the Administration for making this nomination since several other vulnerable Senators running for reelection took a tough, but now meaningless, vote opposing the position of Fraternal Order of Police and several other law enforcement groups—and it’s rarely a good idea to alienate such constituencies, even in the deepest of blue states—and these are all states Mitt Romney won by more than ten points in 2012.  Senator Mary Landrieu of Louisiana, Senator Kay Hagan of North Carolina, and Senator Mark Begich of Alaska voted for the Adegbile nomination and probably bought themselves some political headaches.  And it’s not like President Obama can visit their states and campaign for them to make up for it, since his visit would simply be a reminder of this and other tough votes, like on Obamacare, they have cast on his behalf.

In the past, when the Republicans alone could block a nomination, these Democrats’ votes would have been much less significant. It would have been easier for them to vote with their party or avoid the vote altogether. There would be practically no family fights among the Democrats on the issue of nominations. Granted, without the filibuster, more of the President’s nominees will be confirmed, and more quickly, but sometimes rejections can be almost as memorable as confirmations.

The New York Times recently reported that Senator Mitch McConnell might restore the filibuster for nominees if the Republicans take the Chamber next Congress. Right about now, Harry Reid might feel like seconding that motion.