Washington (CNN) Eleven years after Barack Obama and Hillary Clinton used Senate hearings as an anti-Iraq war launchpad for their presidential ambitions, two Democratic senators are similarly seizing on the Supreme Court battle to play to the gallery of 2020 primary voters.

Brett Kavanaugh's confirmation hearing has given California Sen. Kamala Harris and New Jersey Sen. Cory Booker an opportunity to show the Democratic base they can put up a fight against President Donald Trump while the national television cameras are running.

The two have seized the moment, upending the conversation around the hearing with exchanges that demonstrated qualities at the core of their political appeal: Booker, a willingness to break norms to stand for his principles, and Harris, a long-time prosecutor's ability to undermine a cagey witness.

It comes in one of the last major Senate fights before major Democratic 2020 presidential candidates are expected to launch their campaigns after November's midterm elections.

Republicans have complained that Harris and Booker are posturing with 2020 in mind. They pointed to emails each sent to supporters this week asking for signatures opposing Kavanaugh -- a common tactic to build email lists that can later be used for fundraising and organizing. Their moves infuriated Republicans who accused both of deception, saying Booker and Harris used misleading tactics to score political points.

Republican National Committee Chairwoman Ronna McDaniel tweeted that Booker was "using his crocodile tears as a ploy to raise money. It's pathetic." Texas Republican Sen. John Cornyn said that "it is all about the 2020 Democrat presidential primary."

Yet the aggressive tactics of Booker and Harris were praised by progressives and Democratic strategists who have long complained that Senate Democrats weren't doing enough to slow or stymie Trump's judicial nominees.

"No more butter knives to a gunfight," former Hillary Clinton 2016 campaign aide Brian Fallon tweeted of other Democrats on the Judiciary Committee saying they backed a Booker move on Thursday morning.

No more butter knives to a gunfight.https://t.co/6sjKzvfOmp — Brian Fallon (@brianefallon) September 6, 2018

Reminiscent of Obama vs. Clinton

The spectacle of Harris and Booker playing to potential primary voters recalls an earlier implicit duel between Democratic giants eyeing the White House in Senate committee rooms over a decade ago.

In September 2007, Iraq war commander General David Petraeus and the US ambassador to Baghdad arrived on Capitol Hill to argue that the surge of troops ordered by President George W. Bush was working.

Obama and Clinton, who had both already launched their presidential campaigns, used the occasion to showcase their positions on the war, which was deeply unpopular with Democratic voters, in an audition of commander-in-chief credentials.

In a Senate Foreign Relations Committee hearing, Obama -- who famously opposed the war from the start -- gave a speech attacking Bush for a "disastrous foreign policy mistake." Obama then complained to the committee chairman Sen. Joe Biden -- who later became his vice president -- that he had used up almost all his time and had none left to ask questions.

Later the same day, Clinton seized the chance to go after Petraeus in a hearing of the Senate Armed Services Committee -- and to try to ease suspicions among Democratic primary voters over her vote in 2002 to authorize the war.

She told Petraeus that the surge was a "failed policy" and said Petraeus's upbeat reports of success required "a willing suspension of disbelief."

In the same hearing, Republican presidential contender Sen. John McCain took aim at colleagues who wanted to withdraw troops from Iraq -- a central issue of the 2008 campaign.

The exchanges on Capitol Hill, prompted an attempt by another GOP hopeful -- who has re-emerged in modern day politics in another role -- to get in on the act: Rudy Giuliani.

The former New York mayor accused Clinton of launching a "character assassination" of Petraeus and tried to link her to a newspaper ad taken out by MoveOn.org that branded him "General Betray US."

JUST WATCHED Booker to Cornyn: Bring it Replay More Videos ... MUST WATCH Booker to Cornyn: Bring it 03:03

Booker: 'Bring it'

Progressives demanded a fight against Kavanaugh, and Booker arrived Thursday morning ready to deliver.

Booker released 12 pages of Kavanaugh emails on the topic of racial inequality after complaining that too many documents had been deemed "committee confidential" and shielded from the public eye as the Senate. What he didn't say at the time was that the committee had cleared those documents in the wee hours that morning.

But there was a show.

Cornyn told Booker the punishment under Senate rules for releasing "committee confidential" documents was expulsion from the chamber.

Booker responded by challenging majority Republicans to kick him out.

"Bring it," Booker said. "Then apply the rule and bring the charges. Bring it."

Booker called it "the closest I'll probably ever have in my life to an 'I am Spartacus' moment." And his Democratic colleagues on the Judiciary Committee backed his move.

"Let's jump in this pit together," said the Senate's No. 2-ranking Democrat, Dick Durbin of Illinois.

"Count me in, too," said Hawaii Sen. Mazie Hirono.

Harris hones in on Mueller probe

Until Booker stole the stage Thursday morning, Harris had provided what could prove to be the hearing's most important moment yet.

On Wednesday night, Harris grilled Kavanaugh about whether he had conversations with anyone at Kasowitz Benson Torres, the law firm founded by the President's personal attorney. Kavanaugh repeatedly dodged, insisting that he needed a list of all the firm's employees before saying he didn't remember any such conversations. At one point, he asked Harris if she was thinking of anyone in particular.

"I think you're thinking of someone and you don't want to tell us," she shot back.

Thursday, she came back to the topic, saying she had "reliable information" there had in fact been a conversation.

"I'm sure you've noticed your lack of a clear answer to a question I asked you last night has generated a lot of interest," Harris said. "I received reliable information that you had a conversation about the special counsel or his investigation with the law firm that has represented President Trump."

This time, Kavanaugh responded directly to Harris's question, saying that "the answer is no."

She also grilled Kavanaugh on a series of issues important to progressives. Kavanaugh declined to directly answer whether the Supreme Court case legalizing same-sex marriage was correctly decided by the court, or whether major obstacles to abortion are unconstitutional.

He also wouldn't say whether there are fundamental familial rights for immigrant families -- a question related to the Trump administration's policy of separating undocumented immigrant families at the border -- and whether the President can use race as a basis to ban entry into the United States.

On Wednesday night, Harris also made headlines for her question on abortion rights and the future of Roe v. Wade -- a topic other Democrats angling to run for president who aren't on the committee, including New York Sen. Kirsten Gillibrand, have highlighted.

"Can you think of any laws that give government the power to make decisions about the male body?" Harris asked.

"I'm not thinking of any right now, senator," Kavanaugh responded.