Leading Democrats on Sunday took Republican senators to task for signaling how they'll vote in the all-but-certain Senate impeachment trial — where attention is already turning as the impeachment proceedings facing President Donald Trump move forward.

Sen. Sherrod Brown, D-Ohio, Referring to Senate Majority Leader Mitch McConnell, R-Ky., said on CNN's "State of the Union": "I share the outrage about McConnell, as the leader of the Republican Party, the majority leader in the Senate, saying: 'We're going to get this over with.'"

"We take an oath saying that — at the beginning of the trial — that we will look at the evidence, Brown said, adding:

"And for the leader of the United States Senate, Mitch McConnell, to say he's coordinating with the White House to make sure he's not convicted and removed is — I just — it really is part of this 'see no evil, hear no evil.' It's why I'm so disappointed in my colleagues, this 'see no evil, hear no evil' attitude, that they don't want to look at anything to — that might disagree with their world view of Republicanism and this president."

The House Judiciary Committee passed two articles of impeachment against Trump along party lines late last week — one alleging abuse of power in pushing for Ukraine to investigate former Vice President Joe Biden, his son Hunter Biden and other Democrats, and another alleging obstruction of Congress in withholding information as the House investigated that conduct.

Those articles are expected to be approved soon in a vote before the full House. Impeachment would then move to the Senate, where there is "no chance" that 67 senators would vote to remove Trump from office, McConnell said in an interview Thursday with Fox News.

"Everything I do during this, I'm coordinating with White House counsel," McConnell said in an interview with Fox News host Sean Hannity on Thursday, adding that he would be in "total coordination" with the White House.

"There'll be no difference between the president's position and our position as to how to handle this," he said.

Similarly, Sen. Lindsey Graham, R-S.C., called the impeachment effort "a crock."

"I want to end it," Graham said in an interview that aired Sunday on CBS's "Face the Nation," adding: "I have nothing but disdain for this."

As similar GOP statements have mounted, Democrats and others have pointed to the oath that all senators will take before any Senate trial, in which they are to state: "I solemnly swear that, in all things appertaining to the trial of the impeachment of Donald John Trump, president of the United States, now pending, I will do impartial justice, according to the Constitution and laws, so help me God."

"It isn't just the president who's on trial in an impeachment proceeding. The Senate is on trial," Sen. Dick Durbin, D-Ill., said on "Face the Nation," adding: "I hear people like Senator McConnell talking about the fact he sat down with folks at the White House, he's already made his decision even before he's taken his oath to promise impartial justice. He sees no need for us to spend a lot of time."

Speaking with ABC's "This Week," House Judiciary Committee Chairman Jerrold Nadler, D-N.Y., said the comments he'd heard from McConnell and Graham amounted to a "violation of the oath they're about to take, and it's a complete subversion of the constitutional scheme."

"The Constitution prescribes a special oath for the senators when they sit as a trial in impeachment," Nadler said. "They have to pledge to do impartial justice. And here you have the majority [leader] of the Senate, in effect the foreman of the jury, saying he's going to work hand in glove with the defense attorney."

House Intelligence Committee Chairman Adam Schiff, D-Calif., said on "This Week" that Republicans were making those comments because "they don't want the American people to see the facts."

"They realize what's been presented in the House is already overwhelming, but there's more damning evidence to be had, and they don't want the American people to see that, and I, you know, think that's disgraceful," Schiff said. "But I hope that the senators will insist on getting the documents, on hearing from the witnesses, on making up their own mind even if there are some senators who have decided out of their blind allegiance to this president that he can do nothing wrong, that he can shoot somebody in the middle of the street, and they'd still support him."

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Elsewhere on the Sunday political talk shows, Republicans defended their pretrial judgment, calling impeachment a "political process."

"I fully intend to follow my oath, but the oath of a Senate juror, it has some similarities to a criminal trial, but it has some differences, as well," Sen. Ted Cruz, R-Texas, said on "This Week." "The framers understood that impeachment, particularly the impeachment of a president, is inherently a political exercise. Senators are not required, like jurors in a criminal trial, to be sequestered, not to talk to anyone, not to coordinate. There's no prohibition."

Cruz added that impeachment won't "go anywhere in the Senate because the facts don't back them up."

On "State of the Union," host Jake Tapper pointed out to Rand Paul, R-Ky., the oath that he would soon swear alongside his Senate colleagues. "It doesn't sound like that oath is going to mean very much if you have already made up your mind, sir," he told Paul.

"Well, I would disagree," Paul responded. "I would say that my oath is to the Constitution. And I take that very seriously. So, for example, you can interpret the Constitution in different ways. I interpret the Constitution that we should not be sending foreign aid to other countries. We should be taking care of what we were empowered to do through the Constitution."

Pam Bondi, the former Florida attorney general who recently joined the White House to help handle messaging on impeachment, said on "Fox News Sunday" that the White House should be working "hand in hand" with Republican senators.

"These are the senators who will decide if our president is impeached, which will not happen," she said. "We should and will work hand in hand with them. We wouldn't be doing our job if we weren't working hand in hand with the Senate to clear the president of this charade, this sham that started with Adam Schiff."