Rarely do congressional hearings draw global attention anymore - mostly because it's become a tired, predictable format where witnesses read pre-written statements and lawmakers lob either softball or gotcha questions designed to win favor with a certain constituency or score press attention.
This hearing, scheduled to begin at 10 a.m. ET today, will have all of that - but the subject matter is far more intriguing. The first indication that this is a big deal is the locale, Room 216 of the Senate's Hart Building, a massive space built in the 1970s to accommodate the increasingly mass media nature of Washington. The room includes hundreds of seats for reporters, plus special TV and radio suites that overlook the room - just like press booths used by announcers in sporting arenas.
There are 15 full-time members of the committee - eight Republicans and seven Democrats - and the panel is considered to be one of the last bastions of bipartisanship on Capitol Hill.
The committee is led by Chairman Richard Burr, R-N.C., and Vice Chairman Mark R. Warner, D-Va. Burr is widely credited with leading an above-the-fray investigation that is far more advanced and devoid of partisan bickering than the similar probe underway in the House. Warner has been by his side the entire time.
Burr has said that the single biggest question his panel hopes to answer is what, if any, knowledge Trump had of the purported Russian plot.
"We know that our challenge is to answer that question for the American people," he said when the committee intensified its investigation in March.
"We're going to get it right," Warner added.
Burr is the son of a minister and played football at Wake Forest University. He spent 17 years selling lawn equipment before winning a House seat in 1994. Beyond his current perch, he's known as a quirkier member, known for wearing loafers with no socks and owning a Volkswagen Thing that he parks prominently near the U.S. Capitol.
Warner is a Connecticut native who attended George Washington University and worked on Capitol Hill before becoming a multimillionaire technology executive and then launching his political career.
Burr became committee chairman in 2015 when Republicans seized control of the Senate. Warner became top Democrat on the panel this year when Sen. Dianne Feinstein, D-Calif., dropped one slot in the pecking order so she could take the top Democratic seat on the Judiciary Committee. Democrats see the new assignment as a way to keep Warner - a former governor who has admitted to presidential aspirations - happy, and to help him fully embrace his senatorial role.
While Burr is mostly keeping his head down and trying to avoid making much of a splash, Warner is far more willing to call out Trump's comments and actions. Warner has been especially distressed by reports that Trump criticized Comey during his meeting with Russian officials in the Oval Office last month.
Today's hearing will present a huge global stage for the committee's members - perhaps the biggest of their careers. And yet most committee members are not familiar faces beyond Washington, so here's a review of who they are and how they might use their allotted time.
REPUBLICANS: James E. Risch, Idaho: One of Trump's biggest supporters on Capitol Hill, he is likely to use his question time to press Comey more aggressively than others about why he didn't take steps sooner or publicly to raise concerns with the president's statements and alleged attempts to quash the FBI probe. Risch is among the Republicans especially concerned about ongoing leaks to the news media. In recent interviews, he's called on the Justice Department to root out the "weasel" leaking the information. He's served on the panel since 2009 - making him one of the longer-serving members.
Marco Rubio, Fla.: The former presidential candidate is among the Republicans willing to criticize Trump publicly. But he dined with Trump at the White House on Monday night - a sign that he's also eager and willing to maintain ties to his former rival.
The tone that Rubio takes during his allotted time could give early indications of how much trouble Trump faces with fellow Republicans. For example, Rubio's aggressive questioning of Rex Tillerson at his January confirmation hearing to serve as secretary of state signaled that the former oil executive faced an uphill battle to convince GOP senators that he was up to the job. The senator earned a seat on the committee after his 2010 election, an assignment that allowed him to start building national security credentials ahead of his 2016 presidential bid.
Susan Collins, Maine: On the committee since 2013, Collins is also among the president's most vocal critics in regards to the Russia affair - so her turn on the dais will also be worth watching. She is eager to quiz Comey about Trump's comment that the former director had told the president "on three separate occasions" that the president wasn't the subject of the FBI investigation.
"I find that phrase to be very curious," she said this week, adding that she could "see no reason why" Comey wouldn't be forthcoming on the subject. "It makes a big difference what the exact words were, the tone of the president, the context of the conversation," Collins added later.
Roy Blunt, Mo.: A member of Senate GOP leadership, he's among a handful of senators in both parties who pressured Burr to intensify the committee's investigation of Russian meddling this year. During one particularly intense exchange on the Senate floor in February, Blunt and other senators told Burr that if the intelligence panel didn't step up, other committees would fill the void. But Blunt has signaled that he plans to press Comey to explain himself.
"I haven't frankly understood much of what Comey has done since about a year ago. And his decisions have been, I think, highly questionable," he told "Fox News Sunday." Blunt served on the committee during his first two years in the Senate (2011-2012) and rejoined the panel in 2015 after serving in the interim on the Senate Armed Services Committee.
James Lankford, Okla.: The Oklahoma senator joined the committee in 2015 and is among those that welcomed Comey's firing. But he's a staunch defender of the committee's Russia probe, even in the face of criticism that it is complicating Trump's presidency. He said he's focused on how Russia's meddling may have hampered the nation's public institutions. Comey's testimony "will hopefully help end speculation & lead us to facts," he tweeted last week.
"If there is any American that is engaging with a foreign power to try to affect our elections, that's a real problem. . . . We've got to clear them up both for the sake of the president and the presidency," he also told "CBS This Morning" last week.
Tom Cotton, Ark.: A staunch supporter of Trump's foreign policy, he also dined with the president Monday at the White House. He's cast doubt on the reports of Trump and Comey's interactions and whether the president asked the director to back off Flynn.
"The accounts of these memos he allegedly wrote would be at least triple hearsay, what Donald Trump said, according to Jim Comey, according to someone who saw the memo, according to the New York Times' reporter who had it read to him, didn't even read it," Cotton told "The Hugh Hewitt Show." "So I don't know what Mr. Comey will say on any of these matters beyond what he said to Congress in the past."
John Cornyn, Texas: The second-ranking Republican senator, he's also a Trump ally and far less willing to be critical of the president - other than to voice concern with how the investigations and Trump's response distract from Republican legislative priorities.
"This is sort of a new world with Russian involvement in one our most democratic of institutions, that is the election," he told a San Antonio radio station last week. "People can make allegations. They can guess, they can gossip but none of that really matters. What we need to do is get to the bottom of it and get the facts, and that's what we're going to do."
DEMOCRATS: Dianne Feinstein, Calif.: The former committee chairwoman is the only member who also sits on the Judiciary Committee, which has oversight of the FBI, Comey's former employer. She's also one of the few lawmakers who got a personal heads-up from Trump that he was dismissing Comey.
She said this week that she thinks Comey's testimony "is getting overexaggerated."
"It's an opportunity for Director Comey to say everything he wants to say in the way in which he wants to say it and for us to ask him some questions," she said.
But she has described herself as "incredulous" over Comey's dismissal and is likely to use her time to give Comey the time and space to explain his interactions with Trump.
Ron Wyden, Ore.: He's one of the longest-serving committee members, on the panel since 2001. He's also known as a fierce critic of the intelligence community and has sparred with Comey in the past. But now he's eager to give the former director a chance to share his side of the story. Expect him to serve up volleys that give Comey time to share his thoughts.
"Having more details - fleshing out what was said, who was involved, was it documented - I think will very much clarify where things were at the time Mr. Comey was fired," Wyden said this week. "I said an hour after the president had fired Mr. Comey the single most important thing now is to get Mr. Comey in front of a public forum, the Intelligence Committee. We're getting that now."
Martin Heinrich, N.M.: An engineer by training, the New Mexico senator keeps a low profile but has been on the committee since he joined the Senate in 2012. Unlike some colleagues more interested in grandstanding, Heinrich usually uses his question time to extract actual information. He also regularly challenges witnesses for not being more forthcoming with information. During Wednesday's contentious hearing with top national security officials, Heinrich repeatedly pressed them to share details of their interactions with Trump, to no avail.
Recently, it was Heinrich who got FBI acting director Andrew McCabe to dispute assertions by Trump and his aides that the FBI rank-and-file had lost faith in Comey. "Director Comey enjoyed broad support within the FBI and still does today," McCabe told Heinrich.
Angus King, Maine: The committee's only independent senator will probably be one of the more matter-of-fact and studious inquisitors. King has been totally uncompromising in promoting the committee's probe in the face of pressure from the FBI.
The Comey testimony "is a step in the process for the investigation," he said this week. "I don't think we should assume the world is going to look different the next day. We're going to gain some information I hope and that will be part of all the information we're assembling."
Joe Manchin III, W.Va.: He's the only committee member to have outsourced his question-writing - well, sort of. Manchin asked West Virginians last week to submit questions he could ask Comey during the hearing - a rare move for a senator, but perhaps understandable given that Manchin is up for reelection next year.
"The question for West Virginians is, 'If you knew, or you thought that there was obstruction of justice, why didn't you act on it?' " Manchin told CBS this week. "What were his concerns and if there were deeper concerns, why wasn't anything done at that time?"
Manchin added that he wants to know, if Comey was so concerned by what Trump told him earlier this year, why "was that concern filed away and for what purpose?"
Kamala D. Harris, Calif.: The former California attorney general is the only first-term senator on the committee and is often mentioned as a potential 2020 presidential candidate - so Thursday's hearing provides her a huge opportunity to shape early impressions ahead of a potential bid. Remember when then-Sens. Hillary Clinton and Barack Obama quizzed Gen. David Petraeus about the Iraq War in 2007? This is a moment like that for Harris.
Regarding the committee's Russia investigation, "I do become a bit impatient with the case, I do believe we need to pick it up," she told the San Diego Union-Tribune last week.
She wants to press Comey on "whether he was told, in any way, to manipulate the investigation." And she told the San Diego newspaper that she hopes to ask whether Comey believes the FBI's investigation has proceeded appropriately since his departure.
Supporting characters: Don't be surprised if you see Senate Majority Leader Mitch McConnell, R-Ky., Senate Minority Leader Charles E. Schumer, D-N.Y., and Sens. John McCain, R-Ariz., and Jack Reed, D-R.I., show up to ask questions or take a seat on the dais. All four are "ex officio" members of the committee given their Senate leadership positions (McConnell, Schumer) or leadership of the Senate Armed Services Committee (McCain, Reed).
Other senators who are not members of the committee, including Richard Blumenthal, D-Conn., have said they may come and watch the hearing in person.
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