The hearings for the second impeachment trial of former President Trump start on Tuesday and Republicans are making it clear, even before they're gaveled in, that they believe the result is predetermined. 

"It's a partisan farce," Sen. Rand Paul, R-Ky., said of the impeachment effort on "Fox News Sunday." Paul added that he does not believe it's possible Trump will be convicted. 

"Zero chance of conviction," Paul said when asked if he thinks there's a chance the Senate could meet the 67-vote threshold to convict Trump. "Forty-five Republicans have said it's not even a legitimate proceeding so it's really over before it starts. As far as witnesses, I think unlikely to be witnesses; if they do want witnesses, there's going to be so much evidence that the president had nothing to do with this."

Indeed, Paul last month raised a point of order in the Senate alleging that the impeachment trial is unconstitutional. This forced a vote and only five Republicans joined the Senate's 50 Democrats in saying that the trial is constitutionally allowed to move forward. That means that 12 Republicans would have to change their minds on whether the trial is constitutional for Democrats to have even a chance of convicting Trump. 

Former President Donald Trump speaks to a crowd before boarding Air Force One at Andrews Air Force Base, Md., Wednesday, Jan. 20, 2021. (AP Photo/Luis M. Alvarez)

Former President Donald Trump speaks to a crowd before boarding Air Force One at Andrews Air Force Base, Md., Wednesday, Jan. 20, 2021. (AP Photo/Luis M. Alvarez)

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Sen. Chris Murphy, D-Conn. ‒ who is in favor of convicting Trump and made the case on "Fox News Sunday" that the Senate has a responsibility to hold a trial of the former president ‒ even allowed that Paul makes a reasonable point that the trial is unconstitutional. 

"I admit this is of course a matter of first impression and so I don't think the case that Senator Paul is making is a ridiculous one," he said. 

Other top Republicans also believe Trump is highly unlikely to be convicted, which if it does happen, could result in him being barred from holding office in the future.

"They know that this has no chance of winning. There's no chance of the president actually being convicted here," Trump 2020 senior adviser Jason Miller said on Fox News Sunday. "This is designed to try to implement political pain, so to speak, over the course of a week, maybe a week and a half, and then they're going to move on. They're not even taking this seriously."

Sen. Bill Cassidy, R-La., meanwhile, criticized the process of the impeachment in the House, saying it tainted proceedings in the Senate. 

"Let's face it, the House did an incredibly poor job of building a case before the impeachment vote," he said on NBC's "Meet the Press." "There was no process. I mean, it's almost like, you know, if it happened in the Soviet Union, you would have called it a show trial."

Former White House chief of staff Mark Meadows said on "Sunday Morning Futures" that the trial is "designed for nine House Democrats to do two things — to get political vengeance and have a viral moment."

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Sen. Pat Toomey, R-Pa., added on CNN that because 45 Republicans have already said the trial is unconstitutional, "you can infer how likely it is that those folks will vote to convict."

As for Sen. Lindsey Graham, R-S.C., he said "the outcome is not really in doubt."

"Impeachment is a political process. We've never impeached a president once they're out of office. I think this is a really bad idea. Forty-five-plus Republicans are going to vote early on that it's unconstitutional. It's not a question of how the trial ends. It's a question of when it ends," Graham said on CBS' "Face the Nation." "The only question is will they call witnesses? How long does the trial take?"

Graham also said that he does not endorse the events of Jan. 6 and didn't walk back his previous statements holding Trump partially responsible for the attack on the Capitol. But Graham said he does not believe Trump actually committed a crime, and that the trial itself should not be moving forward.

"It's not a crime. The House is impeaching him under the grounds that his speech created a riot," Graham said. "If you believe he committed a crime, he can be prosecuted like any other citizen. Impeachment is a political process. We've never impeached a president once they're out of office."

Trump's trial stems from an impeachment vote in the House on Jan. 13, one week after a pro-Trump mob stormed the U.S. Capitol. Trump for months made false claims that he won the presidential election before gathering a massive crowd in Washington, D.C., on Jan. 6, the day Congress was set to certify the presidential election results. Trump said the rally would be "wild."

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During that speech, Trump doubled down on his false claims about the election and said, "If you don’t fight like hell, you’re not going to have a country anymore." Trump did tell his followers to march "peacefully and patriotically" to the Capitol, but those who favor his impeachment and conviction say the balance of his post-election behavior and his comments at the rally made clear the president was the cause of the violence at the Capitol. Trump's lawyer, Rudy Giuliani, called for "trial by combat" on the very same stage that morning. 

After the rally ended at 1:12 p.m., and Trump told his followers to "walk down," the Capitol began to be locked down as the attack intensified shortly after 2 p.m. 

"The President of the United States summoned this mob, assembled the mob, and lit the flame of this attack," Rep. Liz Cheney, R-Wyo., said of her vote to impeach Trump last month. "Everything that followed was his doing. None of this would have happened without the president."

Even though the final outcome is very clear on the eve of the Senate's impeachment trial, what's less clear is the path the Senate takes to conviction. 

Senate Majority Leader Chuck Schumer, D-N.Y., and Minority Leader Mitch McConnell, R-Ky., have yet to announce an agreement on how the hearings for the trial itself will work. The only thing that is currently known is that the affair will gavel-in at 1 p.m. on Tuesday and that Sen. Patrick Leahy, D-Vt., will oversee the proceedings. 

What's unknown, as Graham said, is how long the trial will last, if there will be witnesses, how the trial will be structured as it's happening, and if the Senate will split its time between tackling legislation and nominations and holding the trial, or if it will only take care of trial proceedings. 

SEN. MURPHY: 'WE HAVE A CONSTITUTIONAL RESPONSIBILITY' TO HOLD TRUMP'S TRIAL

Murphy said he hopes the Senate will split its days between the trial and other business, saying, "the Senate can walk and chew gum at the same time."

A potential agreement for a trial framework is being shopped around to senators to see if they could agree on it. The trial would start with four hours of debate on whether the trial is constitutional, then a vote on whether to proceed. There also could be debate and a vote on if impeachment managers can call witnesses, which would be subject to a simple majority threshold.

And the trial framework would be modified from six days per week with Sundays off to six days per week with Saturdays off. Trump lawyer David Schoen observes the Jewish Sabbath, so he's requested that the trial stop by 5 p.m. Friday and resume Sunday. 

Murphy also argued that it's constitutional for the Senate to move ahead with the trial and it's not critical there be witnesses at the Senate trial, but they should be allowed if the impeachment managers request them. 

"There is clear precedent for the Senate moving forward on impeachment trial once being sent articles, even after an official has left office and so, you know, my analysis here sort of begins and ends with what is my constitutional responsibility," he said. "This time we saw what happened in real time. President Trump sent that angry mob to the Capitol on live TV, so it's not as important that you have witnesses. But if the House managers want witnesses we should allow them to be able to put them on."

In this Wednesday, Jan. 6, 2021 file photo, supporters of President Donald Trump scale the west wall of the the U.S. Capitol in Washington. The attack on the U.S. Capitol by an angry mob of President Donald Trump's supporters shocked many Americans who thought such a violent assault by their fellow countrymen wasn't possible. (AP Photo/Jose Luis Magana, File)

In this Wednesday, Jan. 6, 2021 file photo, supporters of President Donald Trump scale the west wall of the the U.S. Capitol in Washington. The attack on the U.S. Capitol by an angry mob of President Donald Trump's supporters shocked many Americans who thought such a violent assault by their fellow countrymen wasn't possible. (AP Photo/Jose Luis Magana, File)

Also happening Monday, the House impeachment managers and Trump's defense team will submit a second round of briefs to the Senate, as part of a pretrial deal struck between McConnell and Schumer. Those briefs should provide a further window into how each side will present its argument after they submitted a round of briefs last week. 

Rep. Maxine Waters, D-Calif., predicted Sunday on MSNBC that the impeachment managers will "make a great presentation."

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"Well, first of all, I know that our impeachment managers are going to do a terrific job. If you take a look at the briefs that they've already exposed somewhat, you will see that they have the information. They have the facts. And they have connected the dots," she said. 

One of the arguments that Trump's defense team is likely to use is comparing Trump's post-election rhetoric to words from various Democrats. This could include comments Schumer made about Supreme Court Justices Brett Kavanaugh and Neil Gorsuch, which caused Chief Justice John Roberts to issue a condemnation of the senator, and comments Waters made previously about what people should do if they see Trump officials in public. 

"They’re not going to be able to go to a restaurant, they’re not going to be able to stop at a gas station, they’re not going to be able to shop at a department store," she said. "The people are going to turn on them, they're going to protest, they’re going to absolutely harass them."

Waters on MSNBC, however, said she has "absolutely" never glorified violence.

Fox News' Edmund DeMarche, Chad Pergram and Talia Kaplan contributed to this report.