"It's been abused, and if it continues to be abused, I am confident the rules will be changed," he said on KNPR, declaring that while it isn't his preference to end the super-majority rule in the Senate, "unless these characters who are filibustering literally everything -- unless they change -- I think that's where we're headed."
Reid said that for now, "the one category we're looking at very closely" is President Obama's nominees to fill three vacant seats on the D.C. Circuit Court of Appeals and, which he argued "is, some say, more important than the Supreme Court."
"We're focusing very intently on the D.C. Circuit," he said. "We need at least one more [seat filled]. There's three vacancies. And that will switch the majority. So we're working on it."
The Democratic leader made clear that his aim is to shift the ideological balance of power on the influential circuit court, which often has the final word on the limits of executive power, and has invalidated various actions by President Obama on issues like labor regulations, environmental regulations and recess appointments.
The court currently has four Democratic-appointed and four Republican-appointed active judges. But five out of its six senior judges, who also hear cases, were selected by GOP presidents. He said President George W. Bush's nominees to the court, which secured its conservative tilt, "have been terrible" and "don't ... deserve to be on any court."
Senate Republicans have coalesced around legislation by Sen. Chuck Grassley (R-IA) to reduce the number of active judges on the D.C. Circuit from 11 to eight, telegraphing a mass filibuster of Obama's three picks. Republicans voted unanimously against Obama nominee Patricia Millett in the Judiciary Committee, who last week cleared the panel on a partisan vote, although they didn't challenge her qualifications.
Obama has so far named one judge to the court, Sri Srinivasan, who in May became the first new judge on the D.C. Circuit since 2006. He was unanimously confirmed by the Senate.
Reid made clear he's not currently considering changing the filibuster rules for legislation. And it's far from clear Democrats will be able to muster the necessary 50 votes to scrap the blocking tactic for judicial nominees via the nuclear option.
"The filibuster is not part of the Constitution," Reid told KNPR on Friday.