The historic impeachment vote in the House of Representatives on Wednesday has become a foregone conclusion: all but a few Democrats, most likely joined by zero Republicans, will vote to impeach President Trump.

For a time, House Democrats had hoped that the vote in the GOP-controlled Senate would not be a foregone conclusion in the president’s favor. There was some optimism that moderate Republicans might vote to convict Trump after a trial—perhaps not in the numbers required to remove him, but at least enough to render him a damaging, bipartisan judgment.

But those hopes took a hit in the past week, and now those same Democrats are figuring out ways to cope with a cold, bitter January of disappointment.

As recently as last week, some House Democrats were still theorizing how the GOP majority leader, Sen. Mitch McConnell (R-KY), could be pressured by moderate members of his conference to conduct a longer trial in the Senate, opening up the possibility of new, game-changing documents and testimony.

But as the Senate begins preparing in earnest for a January impeachment trial, the hope has collapsed among Democrats as the president, McConnell, and other key Republicans have coalesced around the idea of a short trial that would feature no new witnesses. Not only that, the GOP leader has dismissed the notion that senators are impartial jurors, calling the trial a “political process,” and openly talking about coordinating the chamber’s proceedings with the White House.

For the House Democrats who have led the impeachment investigation for months, it’s been a deflating, albeit predictable, turn of events as they slowly realize the impeachment trial is increasingly unlikely to yield any kind of surprises or 11th-hour bombshells.

In preparation for the disappointment, some top Democratic lawmakers are already downplaying the role the Senate will play. “At the end of the day, the most important jury will not be Mitch McConnell, Lindsey Graham, and the Republican-controlled Senate, but it will be the American people,” said Rep. Hakeem Jeffries (D-NY), the fourth-ranking House Democrat.

And other Democrats, like Rep. Tom Malinowski (D-NJ), challenged the notion that the Senate trial is a zero-sum game. “The choice in the Senate isn’t a binary between acquittal and removal,” said Malinowski. “What's important is what message is ultimately sent to the American people and to future presidents, about the legitimacy of this conduct.”

“The nature of the vote in the Senate will also send the message—is it completely on party lines? Will a majority of senators vote to convict? We don't know. How the country feels about the whole thing the day after is not something we can predict.”

But whatever hope Democrats have for a paradigm-shifting Senate trial rests on the possibility that witnesses could be called—a prospect that looks increasingly slim as the Senate’s leaders begin bickering about the process of determining the ground rules for an impeachment trial.

On Sunday, the Democratic Senate leader, Sen. Chuck Schumer (NY), sent a letter to McConnell asking him to call four witnesses in the trial who had not testified in the House because of a blanket White House ban on cooperating with the inquiry. Schumer asked that McConnell issue subpoenas for testimony from acting White House Chief of Staff Mick Mulvaney, former National Security Adviser John Bolton, and two Mulvaney subordinates, Robert Blair and Michael Duffey. He also asked for subpoenas for a limited set of documents.

The next day, McConnell responded by roundly dismissing Schumer’s call. “The Senate is meant to act as judge and jury,” the senator said. “To hear a trial. Not to re-run the entire fact-finding investigation because angry partisans rushed sloppily through it.” And rank-and-file GOP senators said if witnesses would be called, they would want to start with testimony from people like Hunter Biden and the anonymous whistleblower—individuals who House Democrats dismissed out of hand during their inquiry.

The two Senate leaders will likely meet soon to discuss the rules, which House Democrats hope could yield a better outcome than this week’s back-and-forth. Lawmakers from both sides have pointed out that during Bill Clinton’s impeachment, senators unanimously voted to approve the rules governing his Senate trial.

With that in mind, some Democrats expressed disbelief that certain GOP lawmakers who have been critical of Trump—particularly Sens. Mitt Romney (R-UT) and Susan Collins (R-ME)—would not support getting more evidence and advocate for some degree of fact-finding on the Senate side.

“That's a different vote for Republican senators,” said Rep. Peter Welch (D-VT), an Intelligence Committee member. “Are they going to literally vote against getting information we all know is quite relevant?”

Putting the screws to Republicans over this question appears to be central to Schumer’s impeachment strategy. The Democrat told POLITICO on Tuesday night that the “bottom line is that our Republican friends have a choice, not just Mitch McConnell but all of them… Do they want the facts to come out, or do they want to cover up the truth?”

Realizing that the direction of impeachment could depend on the influence of a handful of GOP moderates is not a particularly desirable place for Democrats. But some of them who are set to take political heat for their votes to impeach are hoping their Republican counterparts might do the same.

“I think certainly there are some senators who realize that this is sort of a generational vote that they'll have to explain to their grandchildren,” said Rep. Elissa Slotkin (D-MI), who represents a Trump-won district in Michigan and announced her support for impeachment this week. “And for that reason, I would hope that they would want as much objectivity in the process as possible. I hope that they urge the majority leader to take up his very serious role in this process and in earnest.”

Though she said she was hopeful things could change, Slotkin said “people are very polarized right now. And while I want to have hope, I'm not holding my breath.”

Many Democrats have argued for months, however, that there is already a preponderance of evidence to justify Trump’s impeachment and removal from office. “The evidence is overwhelming, and if the senators follow their conscience, then some Republican senators should vote to remove,” said Rep. Ted Lieu (D-CA), a Judiciary Committee member.

But Lieu added an important caveat. “I've learned not to predict what Senate Republicans are going to do,” he said. “I have no idea.”