Reforming the Supreme Court and ending the Senate’s legislative filibuster are emerging as litmus test issues by progressive activists intent on addressing the anti-majoritarian biases of those two conservative-dominated institutions.

Joe Biden is on record as opposing both reforms.

During a speech in Philadelphia on Sunday, rather than threatening retaliation with changes to the Senate and Supreme Court, Biden pitched himself as the voice of calm between two parties locked in a procedural arms race.

“Action and reaction, anger and more anger, sorrow and frustration at the way things are in this country now politically,” Biden said. “That’s the cycle that Republican senators will continue to perpetuate if they go down this dangerous path that they put us on. We need to de-escalate, not escalate. That’s why I appeal to those few Senate Republicans, the handful who really will decide what happens. Please, follow your conscience. Don’t vote to confirm anyone nominated under the circumstances President Trump and Senator McConnell have created. Don’t go there.”

But many prominent Democrats are threatening escalation.

Rep. Alexandria Ocasio-Cortez (D-N.Y.), who was not previously a prominent face of the Supreme Court reform movement, jumped on board on Saturday, the day after Ginsburg died. “We should leave all options on the table, including the number of justices that are on the Supreme Court,” she said.

Sen. Ed Markey (D-Mass.) tweeted that if Mitch McConnell violates his own precedent of not filling vacancies in a presidential election year, “when Democrats control the Senate in the next Congress, we must abolish the filibuster and expand the Supreme Court.” Other progressives went there, too, including Julián Castro, Rep. Jerry Nadler (D-N.Y.), and Rep. Joe Kennedy (D-Mass.), who was outflanked on the left by Markey in his losing primary campaign in Massachusetts early this month.

“If he holds a vote in 2020, we pack the court in 2021,” said Kennedy, who will be out of Congress then. “It’s that simple.”

Mondaire Jones, a favorite of progressives who will almost certainly represent the 17th District of New York next year, wrote an essay this week making the case for more justices. “As America’s white supremacist President tries to install a 6-3 partisan, conservative majority on the Supreme Court, we cannot be immobile,” Jones wrote.

But the threat has moved beyond the progressive echo chamber. Even Sen. Chuck Schumer, an institutionalist skeptical of anything cooked up by the left, declared, “Everything is on the table.”

It was only a matter of time before Senate reform and Supreme Court reform became central to Democrats. The ideas have been percolating among liberals for years. Buttigieg and Elizabeth Warren, who was an ardent backer of killing the filibuster, gave the issues new life last year during the Democratic primaries. But the finalists Bernie Sanders and Joe Biden were anti-reform.

“Bernie and Biden talked about these issues less and were reticent about messing with the filibuster,” said Dan Pfeiffer, a former top official in the Obama White House whose recent book, “Un-Trumping America,“ took up the cause of democracy reform. “There was a sense that the other side of this argument won.”

He noted that an important moment on court expansion came when grassroots progressive groups like Sunrise and the climate-focused Justice Democrats endorsed the idea. “It was a fusing of the democracy reform nerds and the grassroots progressives,” Pfeiffer said. “That’s when I started to get more bullish on it.”

Biden hedged a little on filibuster reform in July, telling the New York Times his position is “going to depend on how obstreperous” Senate Republicans become when he’s president.

But ending the filibuster got a big push when Obama endorsed it during his eulogy at John Lewis’s funeral in late July, calling it a “Jim Crow relic.” Sanders immediately jumped on board, tweeting, “President Obama is absolutely right. It is an outrage that modern-day poll taxes, gerrymandering, I.D. requirements, and other forms of voter suppression still exist today. If expanding the Voting Rights Act requires us to eliminate the filibuster, then that is what we must do.” It was the rare instance when Obama pushed Sanders to the left.

In a year of enormous turmoil, these issues began to fade again. But the politics of replacing Ginsburg have laid bare the most anti-democratic features of the American system.

In the White House is a president who lost the popular vote in 2016. In the Senate is a 53-person Republican majority that represents tens of millions fewer Americans than the 47-person Democratic minority.

These two institutions could now create a 6-3 conservative Supreme Court, cementing the dominance of an objectively minority political ideology across all three of these institutions.

Many Democrats argue that complaining about McConnell’s reversal on filling vacancies in an election year is pointless. The rules are what matter, not a politician’s situational ethics. The point was brought home clearly for many Democrats on Sunday, when retiring Sen. Lamar Alexander (R-Tenn.), considered to be something of an elder statesman, made it clear that Republicans would be fools to be bound by their 2016 rhetoric.

“No one should be surprised that a Republican Senate majority would vote on a Republican President’s Supreme Court nomination, even during a presidential election year. The Constitution gives senators the power to do it,” Alexander wrote in a statement.

Politically, Biden is probably wise to cast himself as the one person trying to de-escalate the tit-for-tat over parliamentary procedure and dramatic institutional reform of the Supreme Court. The Biden campaign does not want McConnell to be able to use reform to cast Biden as radical on these issues.

"His point in this moment is, ‘I’m not going to let Rs reframe this debate to be about something it’s not,’” said a senior Biden official. “The focus right now is on this vote and this fight to keep a Trump nominee off the court, which he believes we will win. He’s not going to indulge in hypotheticals that assume we are going to lose this fight.”

But if he does lose the court fight and win the election, Biden will be under intense pressure to side with the new democracy reform advocates intent on bringing historic change to the Senate and the Supreme Court.