We knew the hearing for Supreme Court nominee Brett Kavanaugh was going to be contentious. We didn't know it was going to be this extraordinary.

On Day 1 of the hearing in the Senate, Senate Democrats proposed not even going through with it. With Kavanaugh seated and the cameras rolling, they interrupted opening statements from the Senate Judiciary Chairman Charles E. Grassley (R-Iowa) to suggest ending the hearing right then and there.

Their main gripe: That 42,000 documents from Kavanaugh's time in the George W. Bush White House were dropped Monday night, hours before the hearing began. The last-minute document dump was the last straw for Democrats' broader frustration with how speedily this Republican-led process has been going.

To stop a Supreme Court committee hearing in its earliest moment, minutes before it gets started, is unprecedented in modern memory. And it speaks to the hyper-politicization of the Senate, of the Supreme Court and of pretty much everything in the Trump era — especially President Trump.

"This is something I've never gone through before in 15 Supreme Court nominations,” a clearly aghast Grassley said as Democrats and Republicans went back and forth for more than an hour about whether to start the hearing.

Democrats know that at the end of the day, they're probably going to be on the losing side of this Supreme Court battle. It takes a simple majority in the Senate to approve Trump's nominee to replace former justice Anthony M. Kennedy, and Republicans have a majority, though admittedly slim.

But Democrats also know how much is at stake with their base right now, on a few levels: The hearing is happening two months before an election in which Democrats have a chance to take back majorities in both chambers of Congress — and a chance to blunt any future Trump nominees who could make the court solidly conservative for a generation.

There's also the fact that Kavanaugh could sit on a court, currently evenly split between conservatives and liberals, that might decide whether Trump has to give an interview to special counsel Robert S. Mueller III in the investigation into Russian election interference.

And Senate Democrats and their base haven't forgotten the injustice they felt that Republicans served them during the 2016 presidential election, when Republicans refused to hold hearings on President Barack Obama's pick to replace the conservative Antonin Scalia, who died. This tactic blocked the nomination of Appeals Court Judge Merrick Garland and ultimately resulted in Trump's appointment of Justice Neil M. Gorsuch.

All that helps explain why Kavanaugh is one of the most unpopular Supreme Court nominees in recent memory, with views about him split almost entirely along partisan lines. And it's important political context with which to view this extraordinary fight over whether to even start a hearing for a Supreme Court nominee.

Then there's the process argument that senators are making. The back and forth over documents is long, and at times both sides have overstepped their bounds, but the short version is this:

There really isn't a neutral arbiter of which of Kavanaugh's documents gets released — or when — because there are millions of them from his time as a judge and as a top aide in the George W. Bush White House. The independent agency that keeps and reviews these documents, the National Archives, said it would take until October to get them to the Senate. That's too late for Republicans, who want to have Kavanaugh seated by the time the next Supreme Court term starts in October.

So a lawyer representing the former president is helping review and release Kavanaugh's documents from his time in the White House. But crucially, not the three years Kavanaugh served as the president's staff secretary, a job that allowed him to decide which memos and policy thinkers made it to the president. (Republicans argue he was little more than a traffic cop, which The Washington Post's Fact Checker determined understates the role he played.)

Then, Friday night, the Trump White House said it is withholding 100,000 of the documents that have been released from Kavanaugh's time in the White House, citing executive privilege. Withholding so many documents is something other presidents have considered but is believed never to have happened to this degree.

And on Monday night, hours before the hearing, the other 42,000 documents were released. Republicans said their staff reviewed everything in a few hours, but as Democrats pointed out, that requires an almost inhuman reading speed of 7,000 pages per hour.

Even before the weekend document dump, Democrats were genuinely frustrated with this process. One Senate Democratic aide said he's been on the committee for 13 years and has never worked with a process he's felt was so partisan. “It's painful,” the aide said.

On Tuesday, Senate Democrats made sure Republicans feel some of their pain.