WASHINGTON — Senate Republicans on Wednesday blocked the confirmation of Caitlin J. Halligan, a prominent New York lawyer, to become a federal appeals court judge in the District of Columbia, the second time in two years Republicans have filibustered her nomination.

The Senate, in a 51-to-41 vote, fell well short of the 60-vote threshold needed to cut off debate and bring Ms. Halligan’s nomination to a vote. The largely party-line vote, with only Senator Lisa Murkowski, Republican of Alaska, joining with Democrats in favor of ending debate, was reminiscent of the previous filibuster of Ms. Halligan — another largely party line vote of 54 to 45.

Many Republicans said they oppose Ms. Halligan’s nomination to the United States Court of Appeals for the District of Columbia Circuit because of what they say is her history of legal activism; most specifically, they say that as the solicitor general of New York State, she worked to advance the “dubious legal theory,” in the words of Senator Mitch McConnell of Kentucky, that gun manufacturers could be held legally responsible for criminal acts committed with their guns.

“In short, Ms. Halligan’s record of advocacy and her activist view of the judiciary lead me to conclude that she would bring that activism to the court,” Mr. McConnell, the Republican leader, said on the Senate floor. “Because of her record of activism, giving Ms. Halligan a lifetime appointment on the D.C. Circuit is a bridge too far.”