Klobuchar spent the first half of her seven minutes on Wednesday touting her own legislation, co-sponsored with Republican Senator James Lankford of Oklahoma, to boost the security of American elections. She then pivoted to questioning Barr about why he concluded that Trump’s request of White House counsel Don McGahn to remove Mueller as special counsel did not amount to obstruction of justice. Her performance seemed politically effective; she promoted her own bipartisan efforts on election security while simultaneously asking relevant questions of the attorney general. But Klobuchar broke no new ground, nor did she when she had a few extra minutes toward the end of the hearing.

Booker also began with a big chunk of throat clearing before he got around to asking Barr a question. He focused on Barr’s statement that the American public should “be grateful” that Mueller could find no evidence that the Trump campaign conspired with Russia to influence the election. Booker took exception to that, pointing to findings by Mueller’s team that Trump’s son Donald Trump Jr. was eager to meet with the Russians, even if he did not criminally conspire with them. But Booker’s line of questioning was hard to follow, and he lost time when he misspoke at one point and said “obstruction” when he meant “collusion.”

“I’m not sure what you’re talking about,” Barr told him. The senator had failed to land a blow.

Harris, by contrast, dispensed with any speechifying. She has said that, as the Democratic nominee, she would “prosecute the case” against the president. And on Wednesday, she set about to prove it. As has been her standard practice with Trump nominees and administration officials, she launched right into her questions as if she were cross-examining a witness. As the most junior Democrat on the committee, she was the last of 10 to question Barr. But she covered terrain that no one else had, and an attorney general whose slipperiness and legalistic hairsplitting had frustrated Democrats for several hours finally appeared to be caught off guard.

“Attorney General Barr, has the president or anyone at the White House ever asked or suggested that you open an investigation of anyone?” Harris began. “Yes or no?”

Barr briefly stammered.

“Could you repeat the question?” he asked.

Ultimately, the attorney general said no one had directly asked him to open an investigation, but he allowed that the topic had come up. “I’m trying to grapple with the word suggest,” he told Harris. “I mean, there have been discussions of matters out there that they have not asked me to open an investigation, but …”

The question was relevant, given Trump’s habit of using his Twitter account to demand that Barr’s predecessor, Jeff Sessions, launch inquiries of Hillary Clinton and other Democrats who have criticized him. Her point apparently made, Harris moved on to the Mueller report. She asked the attorney general whether he had reviewed the underlying evidence Mueller’s team had compiled before he reached his conclusion that the president would not be charged with a crime.