From young newbies to the old guards, Democratic senators are clamoring for filibuster reform, and insist that a mass Republican blockade of three judges to the D.C. Circuit Court of Appeals may be the final straw before going nuclear.

“It would mean they’ve totally gone back on what they said when there was a Republican president,” Senate Judiciary Chairman Patrick Leahy (D-VT), the longest-serving member of the chamber, told TPM. “It would be such a reversal that I think there’d be overwhelming pressure to change the rules.”

Leahy — who is leading the Democrats’ advocacy for nominees Patricia Millett, Cornelia Pillard and Robert Wilkins to the court — has repeatedly resisted filibuster reform in the past. But Republicans are changing his mind after they filibustered Millett and show no signs of letting Democrats fill any of the three vacancies on the powerful court.

The No. 2 Democratic senator shares Leahy’s frustrations.

“That is the most egregious example of partisanship at the expense of extremely well-qualified nominees,” said Senate Majority Whip Dick Durbin (D-IL). “I am not just upset — I am angry at the way Patricia Millett was treated.”

TPM asked the Durbin if a triple-filibuster of D.C. Circuit nominees would led to the nuclear option, through which Democrats could change the filibuster rules with a simple majority. “There comes a tipping point,” he said. “So we’ll see.”

Sen. Tim Kaine (D-VA), a former Democratic National Committee chair and Virginia governor, said Republicans are using the filibuster to effectively nullify the law, and therefore forcing Democrats’ hand on rules reform. “I’m very open to rules changes because we can’t allow laws to be nullified,” he said. “And so the D.C. Circuit is an example. … It’s kind of an attempt to nullify the law using the filibuster. So we have to explore rules changes.”

The enthusiasm for reform is highest among newer Democratic senators who haven’t been around long enough to experience a time during which the chamber was functional.

“I’ve advocated abolishing the filibuster,” said Sen. Richard Blumenthal (D-CT), who served as his state’s attorney general for decade. He told TPM that If Republicans block the remaining D.C. Circuit nominees, “it would come close to being the last straw.”

“I support a rules change whether or not the Republicans filibuster these two nominees,” Sen. Chris Murphy (D-CT), told TPM. “Ultimately, I support the Merkley-Udall proposal to move to a true talking filibuster. I just think — listen, we risk being Charlie Brown to their Lucy. I mean, they continue to put the ball in front of us and pull it out as soon as we go to kick it. So at some point, we need to realize that they are not going to play fair on nominees.”

Sens. Jeff Merkley (D-OR) and Tom Udall (D-NM) also revived calls for filibuster reform this week.

That — along with enormous pressure from outside liberal advocates — is what Senate Majority Leader Harry Reid (D-NV) will be facing if Republicans follow through and deny President Barack Obama’s three top judicial nominees an up-or-down vote. Reid flirted with scrapping the filibuster for judges earlier this week, after Republicans filibustered Millett. He filed cloture Thursday on Pillard, the next nominee, setting up a procedural vote Tuesday.

One factor working against filibuster reform is the calendar. Democratic leadership aides expect to spend weeks — potentially well into December — resolving disputes regarding the defense authorization bill, including sexual assault, Guantanamo Bay and Iran sanctions. They also want to force a vote on raising the minimum wage. Then comes the deadline for the budget committee, followed by a Jan. 15 deadline to keep the government funded or face another shutdown, and the need to raise the debt limit again in February or March.

In an ominous sign for defusing the standoff of judges, Sen. John McCain (R-AZ), who earlier this summer led the successful push to avoid the nuclear option for executive branch nominees, said he would filibuster all of the D.C. Circuit nominees.

“It fits the category of extraordinary circumstances,” the senator said. “If [Reid changes the rules] then I would deeply regret it — I’ve been working all these years to prevent it — but if it happens then I think it would be a terrific mistake. … Someday Republicans will be in the majority, and if they set this precedent, they may not like the result. What goes around comes around in this town.”

Sen. Bob Corker (R-TN) told TPM that Republicans don’t take the Democrats’ “nuclear option” threat seriously when it comes to judicial nominees. “Bring it on,” he said.

“Republicans have already blocked two exceedingly qualified nominees to the D.C. Circuit: Caitlin Halligan and Patricia Millett,” Reid said. “I hope my Republican colleagues will not block another qualified nominee when we vote on cloture on Tuesday.”

The only two Republicans who voted to advance Millett were Sens. Susan Collins (ME) and Lisa Murkowski (AK), and they may be willing to judge the other nominees on the merits, too.

“I have not met with either one of them so I’ve got to do a little more due diligence on the nominees,” Murkowski told TPM. “I always base it on qualifications.”