Senate Republicans are filibustering one of President Obama's nominees to the U.S. Circuit Court of Appeals for D.C.
GOP senators accused former New York Solicitor General Caitlin Joan Halligan of being a liberal activist.
"We shouldn't be putting activists on the bench," Senate Minority Leader Mitch McConnell, R-Ky, said.
"We should be putting people on the bench who are committed to an evenhanded interpretation of the law, so everyone who walks into a courtroom knows he or she will have a fair shake," he said. "In my view, Ms. Halligan is not such a nominee."
Democrats, who insisted Halligan's qualifications were outstanding, voted 54-45 in her favor Tuesday -- six votes short of the 60 needed to break a filibuster.
President Obama said he was "deeply disappointed" with the "Republican pattern of obstructionism that puts party ahead of country."
"Today's vote dramatically lowers the bar used to justify a filibuster," he said.