For the first time, Senate Majority Leader Harry Reid (D-NV) has opened the door — slightly — to reforming the filibuster for judges with the so-called nuclear option if Republicans persist in their mass blockade of President Barack Obama’s top judicial nominees.

He pointed out on Tuesday that support for nuking the filibuster is growing among Democrats — even senior party members who have been skittish about it in the past — after Republicans blocked a vote last Thursday on Patricia Millett to the powerful D.C. Circuit Court of Appeals. Liberals are ratcheting up the pressure on Democrats to go nuclear.

“I’m glad that I’m not the only one now talking about this,” Reid told reporters, in response to a question from TPM. “We’ve had the vice president talk about — maybe it’s time to do something. And we have someone who has never, ever been out front on rules change, and that’s Senator [Patrick] Leahy, who’s said that he’s very disturbed by what’s going on.”

He accused Republicans of violating a 2005 agreement under which Democrats allowed several conservative judges on to the D.C. Circuit in exchange for a bipartisan commitment that future nominees wouldn’t be filibustered except for extraordinary circumstances.

“When we had this agreement a number of years ago, and we let all those people on the D.C. Circuit — there was an agreement by 14 senators, most of whom are still here, that there would be no filibustering judges except under extraordinary circumstances,” said a visibly frustrated Reid. “Patricia Millet — there’s nothing — no one has raised a scintilla of evidence about her that she’s not qualified or that she’s in any way not morally equipped for the job. So, I just think it’s a breach of a number of agreements around here.”

Reid’s response was hardly an explicit threat. But it was also a far cry from his no-comment last week before the Millett filibuster. People close to the Democratic leader say his final ounce of patience with GOP obstructionism on nominees dried up this summer and he’s prepared to nuke the blocking tactic with a bare majority vote — the nuclear option — if it continues.

Reid’s comments come as he intends to escalate the fight this week by filing cloture on Obama’s two other nominees to the D.C. Circuit — Cornelia Pillard and Robert Wilkins. Republicans have vowed to filibuster them, too, arguing that none of the three vacant seats on the second highest federal court ought to be filled because it has a relatively low caseload. Democrats have become almost exasperated in responding that the cases the D.C. Circuit handles are unusually complex and the bench needs to be filled.

If Republicans follow through with their filibuster threat, Reid has two choices: suffer a humiliating defeat or go nuclear. He refrained from nuking the filibuster for executive branch nominations in July after Republicans backed down and agreed to confirm seven pending Obama nominees.

“There should’ve been a rules change 18 years ago,” Sen. Tom Harkin (D-IA) told TPM.

But Republicans doubt Reid could deliver the 50 votes needed to eliminate the filibuster for lifetime-tenured judges even if he wanted to (unlike with executive branch nominees, who are temporary), conscious that some Democrats are reluctant to surrender that power.

“I don’t think there’s anybody in our caucus that takes that [threat] seriously,” Sen. Bob Corker (R-TN) told TPM last week, moments after his party filibustered Millett.

“If you’re going to bring up the nuclear threat every time something comes up, people say, ‘Bring it on.’ Go ahead. Go ahead,” said the Republican senator. “At some point, you kinda have to say, look, if you want to, just go ahead and do it. … I don’t think they will.”