One top Republican senator is pressing ahead with legislation to protect special counsel Robert Mueller, despite a vow from Senate Majority Leader Mitch McConnell (R-KY) that he won’t allow the bill to get a vote on the floor.

Sen. Chuck Grassley (R-IA), the Senate Judiciary Committee chair, told reporters on Wednesday that his committee will vote on the bill regardless.

“They got together, so I feel an obligation to keep my word and move forward,” Grassley said. “But I can’t worry about what’s going on on the floor. I’ve just got to do what I can do.”

If the bill can get out of committee, its future is uncertain, especially after McConnell’s promise to block it from getting to the floor. The Senate majority leader has said for months that he doesn’t believe a bipartisan bill to protect Mueller is necessary because he doesn’t think Trump will fire the special counsel, despite Trump’s rhetoric.

Just days after the administration fired FBI Deputy Director Andrew McCabe in March, President Donald Trump furiously attacked special counsel Robert Mueller on Twitter, writing that “the Mueller probe should never have been started,” and that the “the Mueller team” was biased and “a total WITCH HUNT.”

Most Senate Republicans, however, have sided with McConnell, seeming unfazed by the president’s comments when Vox interviewed them last month.

“I know what President Trump tweeted, but President Trump’s management style is such that he likes to say what’s on his mind,” Sen. John Kennedy (R-LA) told Vox last month, repeating a time-worn Trump-will-be-Trump sentiment. “He grows anxious when he has an unexpressed thought.”

It has become increasingly clear that neither the tweeting nor McCabe’s dismissal is enough for Republican leadership in Congress to act to protect Mueller, or his investigation of Russia’s meddling in the 2016 presidential elections, from any major staffing shake-ups.

The bipartisan proposal comes from a group including Sens. Thom Tillis (R-NC), Chris Coons (D-DE), Lindsey Graham (R-SC), and Cory Booker (D-NJ) — and would check Trump’s power to fire Mueller by requiring the decision to be put before a three-judge panel in federal courts.

McConnell has also been clear he thinks Mueller should be allowed to carry out his investigation into Russia’s alleged meddling in full. But he is not prepared to follow that through with legislation.

“I agree with the president’s lawyers that Bob Mueller should be allowed to finish the job. I think it was an excellent appointment,” McConnell said, referring to White House lawyer Ty Cobb’s statement that Trump “is not considering or discussing the firing of the Special Counsel.”

Last month, I talked to five Senate Republicans to see why Congress isn’t taking action and what actions from the White House — if any — would be a red line for Congress to act.

Here are the transcripts of our conversations, lightly edited for length and clarity.

Sen. John Kennedy (R-LA): “If he fired Mr. Mueller. That would be the red flag.”

Tara Golshan

Is there any room for Congress to protect the special counsel’s investigation?

John Kennedy

I don’t think it’s necessary. First, I don’t think it’s constitutional. If President Trump issued an executive order this morning and said Kennedy is off the Judiciary Committee, I don’t think that would be constitutional. I also am not sure it’s constitutional for us to tell the president who he can fire and can’t fire. Having said that, I think it’s all academic — Mr. Mueller isn’t going anywhere.

Tara Golshan

So what would be the red flag? Or the red line to cross? The president has tweeted —

John Kennedy

Well, if he fired Mr. Mueller. That would be the red flag.

Tara Golshan

Do you think there would be consequences in Congress if he did that?

John Kennedy

I think Congress would be very upset. I think Mr. Mueller ought to be allowed to finish his investigation and report to the American people, and I trust the American people to figure it all out. I know what President Trump tweeted, but President Trump’s management style is such that he likes to say what’s on his mind. He grows anxious when he has an unexpressed thought. It’s not a criticism; it’s just the way he is. He likes to say, “Here’s what I’m thinking.”

But you have to judge him by what he does. He hasn’t fired Mr. Mueller. His lawyer says he’s not going to fire Mr. Mueller. I don’t expect him to fire Mr. Mueller. And so I think this is all an academic exercise.

Sen. Pat Toomey (R-PA): “I’m not sure that’s necessary at the moment”

Tara Golshan

I wanted to ask if you saw any room for Congress to act to protect the special counsel’s investigation.

Pat Toomey

I’m not sure that’s necessary at the moment.

Tara Golshan

Why not?

Pat Toomey

Um. Because it’s not. It’s not been terminated or suspended.

Tara Golshan

So the tweets, or McCabe?

Pat Toomey

(Silence, walks away)

Sen. Jeff Flake (R-AZ): “I think it’s time for our leadership to be firm and say this is the red line, don’t cross it”

Tara Golshan

Did you feel the need for Congress to act to protect the Mueller investigation?

Jeff Flake

Well, the problem is that I’m not convinced the two pieces of legislation that have been introduced are constitutional.

Tara Golshan

So what can Congress do?

Jeff Flake

Well, we are still exploring that. One thing that I think leadership needs to do is to firmly state, “You can’t go here,” and communicate that with the president. We want to preempt this; we don’t want to act afterward.

Tara Golshan

It seems like a lot of your colleagues seem unfazed by a lot of these actions. What’s the red flag, if any? Do you see a line being drawn?

Jeff Flake

Not as much lately. He’s closer than ever, it seems. He’s going after Mueller specifically now on Twitter. So I am concerned. I think it’s time for our leadership to be firm and say this is the red line, don’t cross it.

Tara Golshan

But you don’t think there is a constitutional way Congress can act?

Jeff Flake

We are still looking, obviously. I mean, the only remedies afterward, you know, are, well, the ones you know of. So we are still looking. But I’m not sure you can infringe on the executive power like that.

Sen. Bob Corker (R-TN): “Do I think the administration is planning to do it? No.”

Tara Golshan

Do you think there is room for Congress to act to protect the special counsel?

Bob Corker

I would have thought if it were to happen, it would have happened on the [omnibus] — a must-pass piece of legislation.

Tara Golshan

So you think this is something Congress should do?

Bob Corker

Sure. I think — I am just being honest — does something happen anytime soon? I doubt it. Do I think there would be a significant backlash if he were fired? Yes. Do I think the administration is planning to do it? No.

Tara Golshan

It seems like a lot of your colleagues are unfazed. Is there a red line before it gets to actually firing Mueller?

Bob Corker

I guess there could be. But again, the backlash would be very strong if that were to occur. Do I think there is momentum to pass something — honestly, do I think there is? Not really. But the best place would have been to put something in this [omnibus], which is must-pass. I actually suggested that.

But I don’t think anything is going to happen anytime soon. Just being honest.

Sen. Rob Portman (R-OH): “I see no indication from anything the White House has said”

Tara Golshan

Do you think Congress should act to protect the special counsel’s investigation?

Rob Portman

Uh. I think those of us like me who believe Mueller ought to be able to do his work ought to continue to speak out, and I see no indication from anything the White House has said — in fact, just the opposite. They said they are going to respect him doing his job.

Tara Golshan

So you don’t think Congress should act to —

Rob Portman

Well, I don’t know what it would be (elevator door closes).