As the senators on the Judiciary Committee entered their third day of bickering over Brett Kavanaugh’s nomination to the Supreme Court, tensions boiled over and revealed the other fight playing out in the background.

In a heated exchange Thursday morning, Democratic Sen. Cory Booker said he would release an email that had been designated committee confidential. That prompted Republican Sen. John Cornyn to snap, “Running for President is no excuse for violating the rules of the Senate or of the confidentiality of the documents we are privy to.”

“I don’t ever plan on running for president in 2020 or at any point in the future,” North Carolina Republican Thom Tillis quipped minutes later when he also criticized Booker.

During the past few days of hearings, all eyes have been on Kavanaugh. But he’s not the only person being evaluated. Democratic Sens. Booker, Kamala Harris of California and Amy Klobuchar of Minnesota, all widely considered to be potential presidential contenders in 2020, have each used their time in the highly publicized hearings to maximum effect to lay groundwork for a potential campaign.

That has prompted an eye-roll from the Right. “Instead of treating the judge’s hearing seriously, they’re soaking up every minute of camera time to appeal to their far Left base,” said RNC spokesman Michael Ahrens.

Read More: Can President Trump Pardon Himself? Kavanaugh Won’t Say

Each senator played a different role in the dramatic piece of political theater. Booker’s 2020 persona was one of righteous indignation and idealism. During his lofty opening statement on Tuesday, Booker wound from the special counsel investigation to Russian election meddling to labor rights to healthcare to suicide rates among farmers to dark money to Martin Luther King Jr. to the Three-Fifths Compromise of 1787.

“Right now millions of American families are watching this in sincere concern and fear,” Booker said, wearing a blue tie and sounding every bit the presidential candidate. “I’ve heard them, I’ve gotten the calls, I’ve traveled this country. I’ve talked to Republicans and Democrats… I’ve talked to workers all over my state, all over this nation.” (Booker also joked that he was a “trailblazer” because his statement was twice as long as the allotted time.)

The following day, Booker zeroed in on racial injustice in his questioning of Kavanaugh, including pressing him on an email about racial profiling, which is the note that had been marked committee confidential that Booker broke the rule to release Thursday morning. Releasing committee confidential documents could result in expulsion from the Senate, but on Thursday Booker called it an act of civil disobedience and challenged Republican Committee Chairman Chuck Grassley, “Apply the rule. Bring the charges.”

It was a political dare to expel him in a blaze of glory, sure to endear him to voters on the Left. “This is the closest I will ever come to an ‘I am Spartacus’ moment,” Booker said.

“No matter their stage personas, it’s clear that Senators Booker and Harris are not actually interested in hearing from the nominee, but rather want to continue giving their 2020 presidential stump speeches,” said conservative group Judicial Crisis Network’s Chief Counsel Carrie Severino. “They are turning their solemn constitutional duty to advise and consent into a made-for-TV circus.”

It turned out to be even more of a political show than it had first seemed. Hours later, Bill Burck, George W. Bush’s representative who led the review of Kavanaugh’s documents, released a statement saying his office had cleared Booker’s release of the email the previous evening. “We were surprised to learn of Senator Booker’s histrionics this morning because we had already told him he could use the documents publicly,” Burck said.

“Senate Republicans are doing everything they can to distract from their sham process to rush through a Supreme Court justice who will overturn Roe v. Wade, demolish the Affordable Care Act, and protect President Trump from being investigated,” said Kristin Lynch, Booker’s spokesperson. “Cory and Senate Democrats were able to shame the committee into agreeing to make last night’s documents publicly available, and Cory publicly released those documents as well as other committee confidential documents today. And he’ll keep releasing them because Republicans are hiding Brett Kavanaugh’s record from the American people.”

If Booker seemed to be raising his hand for 2020 like the top student in class, Klobuchar was giving a more subtle nod from the back of the classroom. Klobuchar, wearing a blue jacket and top, publicly supported Booker during his act of civil disobedience on Thursday, saying that the hearing was “ramrodded through” for “political reasons.”

And on Wednesday, Klobuchar pointedly used female pronouns to describe the president when she questioned Kavanaugh on hypotheticals about executive power. “You said in our meeting that Congress would likely act quickly if the president does something, in your words, ‘dastardly,’” Klobuchar said. “What about a president who commits murder? Or if she jeopardizes national security?”

Klobuchar’s office did not response to request for comment.

Another woman potentially vying for the top job: Harris. To make her mark on the hearings, Harris demonstrated her past as a prosecutor, highlighting her ability to ask tough questions and make opponents squirm under pressure.

In a nearly eight-minute exchange on Wednesday, Harris grilled Kavanaugh on whether he had ever had a conversation with anyone at the law firm Kasowitz, Benson & Torres, which was founded by Donald Trump’s lawyer Marc Kasowtiz, about Robert Mueller’s investigation. As Kavanaugh hesitated, saying he didn’t remember, Harris said, “Are you saying with all that you remember— you have an impeccable memory, you’ve been speaking for almost 8 hours, I think more, to this committee about all sorts of things you remember— how can you not remember whether or not you had a conversation about Robert Mueller or his investigation with anyone at that law firm? This investigation has only been going on for so long, sir. “

Later, when Kavanaugh continued to stumble over response, Harris said, “I asked the question just a minute ago, I’m surprised you forgot.” And when he asked if Harris had a specific person in mind that he may have talked to, she replied, “I think you’re thinking of someone and you don’t want to tell us.”

It was just the sort of tense exchange in which Harris, the former attorney general of California, thrives. “Under questioning from Senator Harris and Democrats, Judge Kavanaugh has been evasive, failed to answer simple questions, and demonstrated he’s a partisan who has executed a political agenda as a judge,” Tyrone Gayle, press secretary for Harris, tells TIME when presented with Ahrens and Severino’s comments. “It’s no wonder they are attempting to attack those who have questioned his record and his views.”

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Write to Tessa Berenson at tessa.berenson@time.com.