So it’s not surprising that Biden skipped over progressive wish list items like court packing, something he said more than a year ago would cause Democrats to “rue that day.” While some Democrats want him to embrace and advocate court reforms more broadly, one official said privately he saw the speech as designed to address the moment, rather than moments that still might come.

With a steady lead in national and battleground-state polls, the former vice president has also refused to entertain every idea or respond in real time to every pressure point the Trump campaign tries to apply. Biden outright rejected calls to release a list of potential Supreme Court nominees, arguing doing so could sway their decisions and expose them to unrelenting political attacks. (There’s some recent precedent for this: He never confirmed a list, but many of Biden’s vice-presidential contenders came under intense scrutiny, sometimes privately from each other.)

A creature of the Senate for more than three decades, Biden has long argued that once Trump is out of the way some old norms will be restored and the two parties might be able to collaborate. But before Sunday, he’d never tested his own ability to persuade — especially his optimism, despite evidence it's unwarranted — as a presidential nominee in such an explicit way.

“Please, follow your conscience,” Biden urged the small group of Republican senators still weighing whether to act on a nominee under circumstances being driven by Trump and Senate Majority Leader Mitch McConnell. "Don’t go there. Uphold your constitutional duty, your conscience, let the people speak.

"We can’t keep rewriting history, scrambling norms, ignoring our cherished system of checks and balances.”

Biden’s middle-road approach has so far worked for him electorally. Voters seem intrigued by noble notions of bipartisanship more than they do the onerous compromise it requires.

Biden saved his toughest talk for Trump and the Senate leader, though he also called out Lindsey Graham, the Judiciary Committee chair. For Trump, Biden contended, it’s all a game, a play to “gin up emotions and anger." And with Trump, McConnell is trying to, jam through the nomination as “an exercise in raw political power.”

“I don’t believe the people of this nation will stand for it,” Biden said, turning to the hypocrisy of the GOP's quest.

Biden noted that McConnell and other Republicans argued the opposite position when former President Barack Obama nominated Merrick Garland to replace the late Justice Antonin Scalia in 2016.

McConnell, meantime, secured the support of Sen. Lamar Alexander, who is on his way out and had been viewed as a potential swing vote. So far, only a pair of Republican senators have pledged to oppose a confirmation vote before Election Day: Susan Collins of Maine and Lisa Murkowski of Alaska.

Increasingly, Biden's speech is looking like it was aimed at not a group of three or four, but an audience as small as one: Sen. Mitt Romney. If Romney were to oppose McConnell’s push for a quick vote, the majority leader would have no votes to spare — and Vice President Mike Pence would have to step in to break the tie.

Asked about the overtures to Republicans from the National Constitution Center in Philadelphia, Republican strategist Scott Jennings shot back, “lol.”

“If his view of politics is that because Republicans were mean to Obama, they must now be mean to Trump, a president of their own party, grow up,” Jennings said, pointing to Biden and Senate Democratic leader Chuck Schumer’s calls for confirmation hearings for Garland in 2016.

“The constitution gives the Senate a big, independent hand in this deal and conservatives are pretty happy that Mitch McConnell knows how to use it,” Jennings added. “Biden would be better off worrying about the radicals in his party promising to expand and pack the court and impeach the president to stall this out, if he’s worried about norms and fairness.”

If those proposals do worry Biden, he’s trying to direct attention elsewhere. An aide said Biden is closely coordinating with Schumer and House Speaker Nancy Pelosi. They described them as unified in the belief that the Supreme Court fight underscores the importance of the election, particularly around health care during the pandemic, with the Trump administration trying to undermine the Affordable Care Act in the courts.

On ABC’s “This Week” Sunday, Pelosi argued that Trump has sped up the court timeline to rush a nominee in place for a Nov. 10 hearing on Obamacare. “He doesn’t want to crush the [coronavirus]” she said, “he wants to crush the Affordable Care Act.”

However, Pelosi wouldn’t rule out the possibility of launching impeachment proceedings to block the Senate from confirming Trump’s pick, contending Sunday that Democrats possess “arrows in our quiver” to gum up the process. A day earlier, Schumer delivered a similar message.

“Let me be clear: If Leader McConnell and Senate Republicans move forward with this, then nothing is off the table for next year,” Schumer said during a Democratic Caucus call Saturday, warning of possible payback if Republicans fill the seat before January.

Biden said he won't weigh in on the possibility of the Senate confirming a successor to Ginsburg on the eve of the election — or in the lame-duck session this fall should Trump lose. Even going there would concede that Democrats have already lost, he said.

“I’m not going to assume failure at this point,” he said. “I believe the voices of the American people should be heard.”

If Biden's appeal to conscience and reason again came off as quaint or out of touch with the moment, no one can dispute it's worked for him so far.

“It was an old-fashioned appeal to decency,” said Jim Manley, who spent 21 years working in the Senate, a dozen with the late Ted Kennedy and six with former Majority Leader Harry Reid. "He acknowledged the hyper-partisanship out there, but he wanted to cool things down a little bit before it gets really ugly."

Manley added: "What [Biden] said is largely in sync, for better or for worse, with how he’s operated for months.”